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TABLE OF CONTENTS

Filed Pursuant to Rule 424(b)(5)
Registration No 333-122904


PROSPECTUS SUPPLEMENT
(to Prospectus dated April 4, 2005)

1,041,667 Shares

Logo

Common Stock

        Overstock.com is offering 1,041,667 shares of common stock to a single purchaser in a privately negotiated transaction pursuant to this prospectus supplement.

        Our shares are quoted on the Nasdaq National Market under the symbol "OSTK". On April 28, 2006, the last sale price of our common stock as reported on the Nasdaq National Market was $25.88 per share.

        Investing in our common stock involves risks. See "Risk Factors" beginning on page S-4.

        Neither the Securities and Exchange Commission (the "SEC") nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement or the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

May 1, 2006

This document is in two parts. The first part is this prospectus supplement, which describes the terms of this offering of common stock. The second part is the accompanying prospectus, which gives more general information, some of which may not apply to the common stock. If the information in this prospectus supplement varies from the information in the accompanying prospectus, you should rely on the information contained in this prospectus supplement.

You should only rely on the information contained or incorporated by reference in this prospectus supplement or the accompanying prospectus. We have not authorized anyone to provide you with different information. We are not making an offer of these securities in any state where the offer is not permitted. You should not assume that the information contained in this prospectus supplement or the accompanying prospectus is accurate as of any date other than the date on the front of those documents or that any information we have incorporated by reference is accurate as of any date other than the date of the document incorporated by reference. Our business, financial condition, results of operations and prospects may have changed since these dates.


TABLE OF CONTENTS

Prospectus Supplement
   Page
Prospectus Supplement Summary   S-1
Risk Factors   S-4
Forward-Looking Statements   S-21
Use of Proceeds   S-23
Price Range of Common Stock   S-24
Plan of Distribution   S-26
Experts   S-27
Where You Can Find More Information   S-27

Prospectus dated April 4, 2005
 
Page
About This Prospectus   ii
Overstock.com, Inc.    1
Risk Factors   1
Forward-Looking Statements   17
Use of Proceeds   17
Ratio of Earnings to Fixed Charges   17
Description of the Debt Securities   18
Description of Common Stock   28
Description of Preferred Stock   30
Description of the Warrants   30
Description of Stock Purchase Contracts   33
Description of Units   34
Legal Ownership of Securities   36
Plan of Distribution   37
Validity of the Securities   40
Experts   40
Where You Can Find More Information   40
Documents Incorporated by Reference   42

        Overstock.com is a registered trademark, and Worldstock.com, Club O and Overstock.com Wholesale are trademarks, of Overstock.com, Inc. The Overstock.com logo and Worldstock.com logo are also trademarks of Overstock.com, Inc. Other service marks, trademarks and trade names referred to in this prospectus supplement are property of their respective owners.

ii


PROSPECTUS SUPPLEMENT SUMMARY

        The following summary is qualified in its entirety by, and should be read in conjunction with, the more detailed information and our consolidated financial statements and notes thereto appearing elsewhere or incorporated by reference in this prospectus supplement and the accompanying prospectus. This summary does not contain all of the information that you should consider before investing in our common stock. You should read the entire prospectus supplement and the accompanying prospectus carefully.


Our Company

        We are an online "closeout" retailer offering discount brand name merchandise, including bed-and-bath goods, home decor, kitchenware, watches, jewelry, electronics and computers, sporting goods apparel, designer accessories and travel services, among other products. We also sell books, magazines, CDs, DVDs, videocassettes and video games (BMVG). Our company, based in Salt Lake City, Utah, was founded in 1997, and we launched our first Website through which customers could purchase products in March 1999. In September 2004, we launched an online auction site as part of our Website. In January 2005 we opened our travel department offering air, hotel and car reservation services as well as cruise and vacation packages.

Our Business

        We offer our customers an opportunity to shop for bargains conveniently, while offering our suppliers an alternative inventory liquidation distribution channel. In 1999 we offered approximately 100 products on our Website; currently we offer approximately 62,000 non-BMVG products and approximately 725,000 BMVG products under five main tabs: Shopping; Books, Music, Movies & Games; Bulk Buys & Business Supplies; Auctions; and Travel. Products under our Shopping tab are organized into eight departments on our main website, www.overstock.com:

Apparel
Electronics & Computers
Gifts
Health & Wellness		   Home & Garden
Jewelry & Watches
Sporting Goods
Worldstock

        We continually add new, limited-inventory products to our Websites in order to create an atmosphere that encourages customers to visit frequently and purchase products before our inventory sells out.

        We have a "direct" business, in which we buy and take possession of inventory for resale. We also have our "fulfillment partner" business, in which we sell merchandise of other retailers, cataloguers or manufacturers through our Websites. We currently have fulfillment partner relationships with approximately 460 third parties which post approximately 48,000 non-BMVG products as well as most of the BMVG products and a portion of the travel offerings on our Websites.

        During the year ended December 31, 2005, we fulfilled approximately 38% of all orders through our leased Salt Lake City, Utah warehouses or our outsourced warehouses located in Plainfield, Indiana. Our warehouses generally ship between 12,000 and 14,000 orders per day, and up to approximately 34,000 orders per day during peak periods, using overlapping daily shifts. The balance of our orders during 2005 was for inventory owned and shipped by our third-party fulfillment partners.

        We staff our customer service department with dedicated in-house and outsourced professionals who respond to phone, online chat and email inquiries on products, ordering, shipping status and returns. Our customer service staff processes approximately 40,000 calls per week, and processes approximately 30,000 email messages each week, with a turnaround goal of one business day. The

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demands on our customer service staff increase significantly during peak periods, including the several weeks before and after Christmas. As of December 31, 2005, we had 620 full-time employees.

Business Strategy

        Our objective is to become the dominant closeout Internet-based solution for holders of brand-name merchandise, allowing them to dispose of that merchandise discreetly and with high recovery values and ultimately to become a one-stop Internet-based discount shopping destination. Our supplier relationships provide us with recognized, brand-name products. Our manufacturer and supplier relationships are based on historical experience with manufacturers and liquidation wholesalers and do not obligate or entitle us to receive merchandise on a long-term or short-term basis.

Our Corporate Information

        Our principal executive offices are located at 6350 South 3000 East, Salt Lake City, Utah 84121, and our telephone number is (801) 947-3100. We were formed in 1997, and completed our initial public offering in June 2002. Our main Website address is www.overstock.com. The information contained on our Website is not part of this prospectus supplement.

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THE OFFERING

Common stock offered by us   1,041,667 shares.
Common stock to be outstanding after this offering   20,499,551 shares.
Nasdaq National Market Symbol   "OSTK"
Use of proceeds   We will receive net proceeds from the sale of common stock offered by this prospectus supplement of approximately $25,000,000, which we plan to use for general corporate purposes and working capital requirements, including sales and marketing activities and inventory purchases. In addition, we may use a portion of the net proceeds to acquire complementary technologies or businesses. However, we currently have no commitments or agreements and are not involved in any negotiations with respect to any such transactions.
Risk factors   See "Risk Factors" on page S-4 of this prospectus supplement and on page 1 of the accompanying prospectus for a discussion of risks relating to an investment in our common stock.

        The number of shares to be outstanding after this offering excludes shares issuable upon exercise of outstanding options, shares issuable upon exercise of outstanding warrants, shares reserved for issuance upon conversion of our outstanding convertible senior notes, and shares reserved for issuance pursuant to our 2005 Equity Incentive Plan.

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RISK FACTORS

        Any investment in our securities involves a high degree of risk. Investors should consider carefully the risks and uncertainties described below, and all other information included or incorporated by reference in this prospectus supplement or the prospectus and in any reports we file with the SEC after we file this prospectus supplement, before deciding whether to purchase or hold our securities. Additional risks and uncertainties not currently known to us or that we currently deem immaterial may also become important factors that may harm our business. The occurrence of any of the following risks could harm our business. The trading price of our securities could decline due to any of these risks and uncertainties or other unknown matters, and investors may lose part or all of their investment.

Risks Relating to Overstock

We have a history of significant losses. If we do not achieve profitability, our financial condition and our stock price could suffer.

        We have a history of losses and we may continue to incur operating and net losses for the foreseeable future. We incurred net losses attributable to common shares of $4.7 million and $25.1 million for the years ended December 31, 2004 and 2005, respectively. As of December 31, 2004 and 2005, our accumulated deficit was $71.7 million and $96.8 million, respectively. We will need to generate significant revenues to achieve profitability, and we may not be able to do so. Even if we do achieve profitability, we may not be able to sustain or increase profitability on a quarterly or annual basis in the future. If our revenues grow more slowly than we anticipate, or if our operating expenses exceed our expectations, our financial results would be harmed.

        We will continue to incur significant operating expenses and capital expenditures as we:


        Because we will incur many of these expenses before we receive any revenues from our efforts, our losses may be greater than the losses we would incur if we developed our business more slowly. Further, we base our expenses in large part on our operating plans and future revenue projections. Many of our expenses are fixed in the short term, and we may not be able to quickly reduce spending if our revenues are lower than we project. Therefore, any significant shortfall in revenues would likely harm our business, prospects, operating results and financial condition. In addition, we may find that these efforts are more expensive than we currently anticipate which would further increase our losses. Also, the timing of these expenses may contribute to fluctuations in our quarterly operating results.

S-4

If we fail to accurately forecast our expenses and revenues, our business, operating results and financial condition may suffer and the price of our securities may decline.

        Our limited operating history and the rapidly evolving nature of our industry make forecasting operating results difficult. We have recently completed several large, complex and expensive infrastructure upgrades in order to increase our ability to handle larger volumes of sales and to develop or increase our ability to perform a variety of analytical procedures relating to our business, and we are continuing the work to upgrade and further expand these and other components of our infrastructure. We have experienced difficulties with the implementation of various aspects to the upgrades of our infrastructure, and have incurred increased expenses as a result of these difficulties. As a result of these expenditures, our ability to quickly reduce spending if our revenues are lower than we project is limited. Therefore, any significant shortfall in the revenues for which we have built and are continuing to build our infrastructure would likely harm our business, prospects, operating results and financial condition and cause our results of operation to fall below the expectations of public market analysts and investors. If this occurs, the price of our securities may decline.

We depend on our relationships with third party fulfillment partners for a large portion of the products that we offer for sale on our Websites. If we fail to maintain these relationships, our business will suffer.

        At December 31, 2005, we had fulfillment partner relationships with approximately 460 third parties whose products we offer for sale on our Websites. These products accounted for approximately 80% of the non-BMVG products available. We do not have any long-term agreements with any of these third parties. Our agreements with third parties are terminable at will by either party immediately upon notice. In general, we agree to offer the third parties' products on our Websites and these third parties agree to provide us with information about their products, honor our customer service policies and ship the products directly to the customer. If we do not maintain our existing or build new relationships with third parties on acceptable commercial terms, we may not be able to offer a broad selection of merchandise, and customers may refuse to shop at our Websites. In addition, manufacturers may decide not to offer particular products for sale on the Internet. If we are unable to maintain our existing or build new fulfillment partner relationships or if other product manufacturers refuse to allow their products to be sold via the Internet, our business and prospects would suffer severely.

We are partially dependent on third parties to fulfill a number of our fulfillment, distribution and other retail functions. If such parties are unwilling or unable to continue providing these services, our business could be seriously harmed.

        In our fulfillment partner business, although we handle returned merchandise, we continue to rely on third parties to conduct a number of other traditional retail operations with respect to their respective products that we offer for sale on our Websites, including maintaining inventory, preparing merchandise for shipment to individual customers and timely distribution of purchased merchandise. We have no effective means to ensure that these third parties will continue to perform these services to our satisfaction or on commercially reasonable terms. In addition, because we do not take possession of these third parties' products, we are unable to fulfill these traditional retail operations ourselves. Our customers could become dissatisfied and cancel their orders or decline to make future purchases if these third parties are unable to deliver products on a timely basis. If our customers become dissatisfied with the services provided by these third parties, our reputation and the Overstock.com brand could suffer.

S-5


We rely on our relationships with manufacturers, retailers and other suppliers to obtain sufficient quantities of quality merchandise on acceptable terms. If we fail to maintain our supplier relationships on acceptable terms, our sales and profitability could suffer.

        To date, we have not entered into contracts with manufacturers or liquidation wholesalers that guarantee the availability of merchandise for a set duration. Our contracts or arrangements with suppliers do not provide for the continuation of particular pricing practices and may be terminated by either party at any time. Our current suppliers may not continue to sell their excess inventory to us on current terms or at all, and we may not be able to establish new supply relationships. For example, it is difficult for us to maintain high levels of product quality and selection because none of the manufacturers, suppliers and liquidation wholesalers from whom we purchase products on a purchase order by purchase order basis have a continuing obligation to provide us with merchandise at historical levels or at all. In most cases, our relationships with our suppliers do not restrict the suppliers from selling their respective excess inventory to other traditional or online merchandise liquidators, which could in turn limit the selection of products available on our Websites. If we are unable to develop and maintain relationships with suppliers that will allow us to obtain sufficient quantities of merchandise on acceptable commercial terms, such inability could harm our business, prospects, results of operation and financial condition.

We depend upon third-party delivery services to deliver our products to our customers on a timely and consistent basis. Deterioration in our relationship with any one of these third parties could decrease our ability to track shipments, cause shipment delays, and increase our shipping costs and the number of damaged products.

        We rely upon multiple third parties for the shipment of our products. Because we do not have a written long-term agreement with any of these third parties, we cannot be sure that these relationships will continue on terms favorable to us, if at all. Unexpected increases in shipping costs or delivery times, particularly during the holiday season, could harm our business, prospects, financial condition and results of operations. If our relationships with these third parties are terminated or impaired or if these third parties are unable to deliver products for us, whether through labor shortage, slow down or stoppage, deteriorating financial or business condition, responses to terrorist attacks or for any other reason, we would be required to use alternative carriers for the shipment of products to our customers. In addition, conditions such as adverse weather can prevent any carriers from performing their delivery services, which can have an adverse effect on our customers' satisfaction with us. In any of these circumstances, we may be unable to engage alternative carriers on a timely basis, upon terms favorable to us, or at all. Changing carriers would likely have a negative effect on our business, prospects, operating results and financial condition. Potential adverse consequences include:


A significant number of merchandise returns could harm our business, financial condition and results of operations.

        We allow our customers to return products and, beginning July 1, 2003, we started accepting returns of products sold through our fulfillment partners. We modify our policies relating to returns from time to time, and any policies intended to reduce the number of product returns may result in customer dissatisfaction and fewer return customers. If merchandise returns are significant, our business, prospects, financial condition and results of operations could be harmed.

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If the products that we offer on our Websites do not reflect our customers' tastes and preferences, our sales and profit margins would decrease.

        Our success depends in part on our ability to offer products that reflect consumers' tastes and preferences. Consumers' tastes are subject to frequent, significant and sometimes unpredictable changes. Because the products that we sell typically consist of manufacturers' and retailers' excess inventory, we have limited control over the specific products that we are able to offer for sale. If our merchandise fails to satisfy customers' tastes or respond to changes in customer preferences, our sales could suffer and we could be required to mark down unsold inventory which would depress our profit margins. In addition, any failure to offer products in line with customers' preferences could allow our competitors to gain market share. This could have an adverse effect on our business, prospects, results of operations and financial condition.

We face risks relating to our inventory.

        We directly purchase some of the merchandise that we sell on our Websites. We assume the inventory damage, theft and obsolescence risks, as well as price erosion risks for products that we purchase directly. These risks are especially significant because some of the merchandise we sell on our Websites are characterized by rapid technological change, obsolescence and price erosion (for example, computer hardware, software and consumer electronics), and because we sometimes make large purchases of particular types of inventory. In addition, we often do not receive warranties on the merchandise we purchase. Further, beginning July 1, 2003, we started accepting returns of products sold through our fulfillment partners, and we have the risk of reselling the returned products.

        In the recent past, we have recorded charges for obsolete inventory and have had to sell certain merchandise at a discount or loss. It is impossible to determine with certainty whether an item will sell for more than the price we pay for it. Because we rely heavily on purchased inventory, our success will depend on our ability to liquidate our inventory rapidly, the ability of our buying staff to purchase inventory at attractive prices relative to its resale value and our ability to manage customer returns and the shrinkage resulting from theft, loss and misrecording of inventory. If we are unsuccessful in any of these areas, we may be forced to sell our inventory at a discount or loss.

We have grown quickly and if we fail to manage our growth, our business will suffer.

        We have rapidly and significantly expanded our operations, and anticipate that further significant expansion will be required to address potential growth in our customer base and market opportunities. This expansion has placed, and is expected to continue to place, a significant strain on our management, operational and financial resources. Some of our officers have no prior senior management experience at public companies. Our new employees include a number of key managerial, technical and operations personnel, and we expect to add additional key personnel in the future. To manage the expected growth of our operations and personnel, we will be required to improve existing and implement new transaction-processing, operational and financial systems, procedures and controls, and to expand, train and manage our already growing employee base. If we are unable to manage growth effectively, our business, prospects, financial condition and results of operations will be harmed.

The loss of key personnel or any inability to attract and retain additional personnel could affect our ability to successfully grow our business.

        Our performance is substantially dependent on the continued services and on the performance of our senior management and other key personnel, particularly Patrick M. Byrne, our Chief Executive Officer. Our performance also depends on our ability to retain and motivate other officers and key employees. The loss of the services of any of our executive officers or other key employees for any unforeseen reason, including without limitation, illness or call to military service, could harm our

S-7


business, prospects, financial condition and results of operations. We do not have employment agreements with any of our key personnel and we do not maintain "key person" life insurance policies. Our future success also depends on our ability to identify, attract, hire, train, retain and motivate other highly-skilled technical, managerial, editorial, merchandising, marketing and customer service personnel. Competition for such personnel is intense, and we cannot assure you that we will be able to successfully attract, assimilate or retain sufficiently qualified personnel. Our failure to retain and attract the necessary technical, managerial, editorial, merchandising, marketing and customer service personnel could harm our revenues, business, prospects, financial condition and results of operations.

We may be unable to manage expansion into new business areas which could harm our business operations and reputation.

        Our long-term strategic plan involves expansion of our operations to offer additional types of products and services. We cannot assure you that our efforts to expand our business in this manner will succeed. Because we were unable to generate significant traffic for our former B2B site, in the third quarter of 2004, we merged the B2B site into our main website, and opened our Wholesale bulk purchase program. Our failure to succeed in this market or other markets or other product or service offerings may harm our business, prospects, financial condition and results of operation. We cannot assure you that we will be able to expand our operations in a cost-effective or timely manner or that our efforts to expand will be successful. Furthermore, any new business or Website we launch that is not favorably received by consumers could damage our reputation or the Overstock.com brand. We may expand the number of categories of products we carry on our Websites and these and any other expansions of our operations would also require significant additional expenses and development and would strain our management, financial and operational resources. The lack of market acceptance of such efforts or our inability to generate satisfactory revenues from such expanded services or products to offset their cost could harm our business, prospects, financial condition and results of operations.

We may expand our international business, causing our business to become increasingly susceptible to numerous international business risks and challenges that could affect our profitability.

        We have begun to expand into international markets, and in the future we may do so more aggressively. International sales and transactions are subject to inherent risks and challenges that could adversely affect our profitability, including:

        To the extent we generate international sales and transactions in the future, any negative impact on our international operations could negatively impact our business. In particular, gains and losses on the conversion of foreign payments into United States dollars may contribute to fluctuations in our results of operations and fluctuating exchange rates could cause reduced gross revenues and/or gross margins from non-dollar-denominated international sales.

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In order to obtain future revenue growth and achieve and sustain profitability we will have to attract customers on cost-effective terms.

        Our success depends on our ability to attract customers on cost-effective terms. We have relationships with online services, search engines, directories and other Websites and e-commerce businesses to provide content, advertising banners and other links that direct customers to our Websites. We rely on these relationships as significant sources of traffic to our Websites and to generate new customers. If we are unable to develop or maintain these relationships on acceptable terms, our ability to attract new customers and our financial condition could be harmed. In addition, certain of our online marketing agreements may require us to pay upfront fees and make other payments prior to the realization of the sales, if any, associated with those payments. Accordingly, if these agreements or similar agreements that we may enter into in the future fail to produce the sales that we anticipate, our results of operations will be adversely affected. We cannot assure you that we will be able to increase our revenues, if at all, in a cost-effective manner. We periodically conduct national television and radio branding and advertising campaigns. Such campaigns are expensive and may not result in the cost effective acquisition of customers.

        Further, many of the parties with which we may have online-advertising arrangements could provide advertising services for other online or traditional retailers and merchandise liquidators. As a result, these parties may be reluctant to enter into or maintain relationships with us. Failure to achieve sufficient traffic or generate sufficient revenue from purchases originating from third parties may result in termination of these relationships by these third parties. Without these relationships, our revenues, business, prospects, financial condition and results of operations could suffer.

We may not be able to compete successfully against existing or future competitors.

        The online liquidation services market is new, rapidly evolving and intensely competitive. Barriers to entry are minimal, and current and new competitors can launch new Websites at a relatively low cost. Our consumer Website currently competes with:


Our Website competes with liquidation "brokers" and retailers and online marketplaces such as eBay, Inc.

        We expect the online liquidation services market to become even more competitive as traditional liquidators and online retailers continue to develop services that compete with our services. In addition, manufacturers and retailers may decide to create their own Websites to sell their own excess inventory and the excess inventory of third parties. Competitive pressures created by any one of our competitors, or by our competitors collectively, could harm our business, prospects, financial condition and results of operations.

        Further, as a strategic response to changes in the competitive environment, we may from time to time make certain pricing, service or marketing decisions or acquisitions that could harm our business, prospects, financial condition and results of operations. For example, to the extent that we enter new lines of businesses such as third-party logistics, or discount brick and mortar retail, we would be competing with large established businesses such as APL Logistics, and Ltd., Ross Stores, Inc.,

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respectively. We have recently entered the online auctions business in which we compete with large established businesses including eBay, Inc.

        Many of our current and potential competitors described above have longer operating histories, larger customer bases, greater brand recognition and significantly greater financial, marketing and other resources than we do. In addition, online retailers and liquidation e-tailers may be acquired by, receive investments from or enter into other commercial relationships with larger, well-established and well-financed companies. Some of our competitors may be able to secure merchandise from manufacturers on more favorable terms, devote greater resources to marketing and promotional campaigns, adopt more aggressive pricing or inventory availability policies and devote substantially more resources to Website and systems development than we do. Increased competition may result in reduced operating margins, loss of market share and a diminished brand franchise. We cannot assure you that we will be able to compete successfully against current and future competitors.

Our operating results depend on our Websites, network infrastructure and transaction-processing systems. Capacity constraints or system failures would harm our business, prospects, results of operations and financial condition.

        Any system interruptions that result in the unavailability of our Websites or reduced performance of our transaction systems would reduce our transaction volume and the attractiveness of the services that we provide to suppliers and third parties and would harm our business, prospects, operating results and financial condition.

        We use internally developed systems for our Websites and certain aspects of transaction processing, including customer profiling and order verifications. We have experienced periodic systems interruptions due to server failure, which we believe will continue to occur from time to time. If the volume of traffic on our Websites or the number of purchases made by customers substantially increases, we will need to further expand and upgrade our technology, transaction processing systems and network infrastructure. We have experienced and expect to continue to experience temporary capacity constraints due to sharply increased traffic during sales or other promotions and during the holiday shopping season. Capacity constraints can cause unanticipated system disruptions, slower response times, and degradation in levels of customer service, impaired quality and delays in reporting accurate financial information.

        Our transaction processing systems and network infrastructure may be unable to accommodate increases in traffic in the future. We may be unable to project accurately the rate or timing of traffic increases or successfully upgrade our systems and infrastructure to accommodate future traffic levels on our Websites. In addition, we may be unable to upgrade and expand our transaction processing systems in an effective and timely manner or to integrate any newly developed or purchased functionality with our existing systems. For example, in the third quarter 2005 we experienced difficulties with our implementation of infrastructure upgrades, which resulted in our inability to upload new products to our website for a period of approximately five weeks. Any such difficulties with our transaction processing systems or other difficulties upgrading, expanding or integrating various aspects of our systems may cause unanticipated system disruptions, slower response times, and degradation in levels of customer service, additional expense, impaired quality and speed of order fulfillment or delays in reporting accurate financial information.

If the facilities where substantially all of our computer and communications hardware is located fail, our business, results of operations and financial condition will be harmed.

        Our success, and, in particular, our ability to successfully receive and fulfill orders and provide high-quality customer service, largely depends on the efficient and uninterrupted operation of our computer and communications systems. Substantially all of our computer and communications hardware

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is located at a single co-location facility in Salt Lake City, Utah, with a partially redundant back-up system located at our corporate headquarters in Salt Lake City. Although we have designed our back-up system in an effort to avoid or minimize service interruptions in the event of a failure of our main facility, our systems and operations are vulnerable to damage or interruption from fire, flood, power loss, telecommunications failure, terrorist attacks, acts of war, break-ins, earthquake and similar events. We do not have a formal disaster recovery plan and our business interruption insurance may be insufficient to compensate us for losses that may occur. Despite the implementation of network security measures, our servers are vulnerable to computer viruses, physical or electronic break-ins and similar disruptions, which could lead to interruptions, delays, loss of critical data or the inability to accept and fulfill customer orders. The occurrence of any of the foregoing risks could harm our business, prospects, financial condition and results of operations.

We may be unable to protect our proprietary technology or keep up with that of our competitors.

        Our success depends to a significant degree upon the protection of our software and other proprietary intellectual property rights. We may be unable to deter misappropriation of our proprietary information, detect unauthorized use and take appropriate steps to enforce our intellectual property rights. In addition, our competitors could, without violating our proprietary rights, develop technologies that are as good as or better than our technology.

        Our failure to protect our software and other proprietary intellectual property rights or to develop technologies that are as good as our competitors' could put us at a disadvantage to our competitors. In addition, the failure of the third parties whose products we offer for sale on our Websites to protect their intellectual property rights, including their domain names, could impair our operations. These failures could harm our business, results of operations and financial condition.

If we do not respond to rapid technological changes, our services could become obsolete and we could lose customers.

        To remain competitive, we must continue to enhance and improve the functionality and features of our e-commerce businesses. We may face material delays in introducing new services, products and enhancements. If this happens, our customers may forgo the use of our Websites and use those of our competitors. The Internet and the online commerce industry are rapidly changing. If competitors introduce new products and services using new technologies or if new industry standards and practices emerge, our existing Websites and our proprietary technology and systems may become obsolete. Our failure to respond to technological change or to adequately maintain, upgrade and develop our computer network and the systems used to process customers' orders and payments could harm our business, prospects, financial condition and results of operations.

We may not be able to obtain trademark protection for our marks, which could impede our efforts to build brand identity.

        We have filed trademark applications with the Patent and Trademark Office seeking registration of certain service marks and trademarks. There can be no assurance that our applications will be successful or that we will be able to secure significant protection for our service marks or trademarks in the United States or elsewhere as we expand internationally. Our competitors or others could adopt product or service marks similar to our marks, or try to prevent us from using our marks, thereby impeding our ability to build brand identity and possibly leading to customer confusion. Any claim by another party against us or customer confusion related to our trademarks, or our failure to obtain trademark registration, could negatively affect our business.

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We may not be able to enforce protection of our intellectual property rights under the laws of other countries.

        As we continue to expand internationally, we are subject to risks of doing business internationally as related to our intellectual property, including:

Our business and reputation may be harmed by the listing or sale of pirated, counterfeit or illegal items by third parties, and by intellectual property litigation.

        We have received in the past, and we anticipate we will receive in the future, communications alleging that certain items listed or sold through our Websites infringe third-party copyrights, trademarks and trade names or other intellectual property rights or that we have otherwise infringed third parties' past, current or future intellectual property rights. For example, in October 2003, Tiffany (NJ) Inc. and Tiffany and Company filed a complaint against us in the United States District Court for the Southern District of New York alleging that we have distributed counterfeit and otherwise unauthorized Tiffany product in violation of federal copyright and trademark law and related state laws. In addition, in January and February 2005, Tiffany filed additional complaints against us asserting similar claims. We have recently reached an agreement in principle which will settle and dismiss all of the cases. We are currently working on a definitive settlement agreement with Tiffany.

        We may be unable to prevent third parties from listing unlawful goods, and we may be subject to allegations of civil or criminal liability for unlawful activities carried out by third parties through our Websites. In the future, we may implement measures to protect against these potential liabilities that could require us to spend substantial resources and/or to reduce revenues by discontinuing certain service offerings. Any costs incurred as a result of liability or asserted liability relating to the sale of unlawful goods or the unlawful sale of goods could harm our revenues, business, prospects, financial condition and results of operations.

        Resolving litigation or claims regarding patents or other intellectual property, whether meritorious or not, could be costly, time-consuming, cause service delays, divert our management and key personnel from our business operations, require expensive or unwanted changes in our methods of doing business or require us to enter into costly royalty or licensing agreements, if available. As a result, these claims could harm our business.

        Negative publicity generated as a result of the foregoing could damage our reputation, harm our business and diminish the value of our brand name.

Gradient Analytics and Rocker Partners, L.P. Litigation

        In August 2005 we filed an unfair business practice lawsuit against Gradient Analytics, Rocker Partners, L.P. and others, alleging that the defendants have conspired to denigrate Overstock's business for personal profit. In October 2005 we filed an amended complaint alleging additional causes of action and articulating in greater detail the allegations against the defendants. Overstock's President, Dr. Patrick Byrne, has appeared on nationally syndicated television programs and elsewhere to discuss the litigation. The use of management's time and attention in connection with the litigation and related matters may reduce the time management is able to spend on other aspects of our business, which may have adverse effects on other aspects of our business. To the extent that any such adverse effects

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exceed any benefits we may realize from pursuing the litigation, our business, prospects, financial condition and results of operation may suffer.

We may be liable if third parties misappropriate our customers' personal information.

        If third parties are able to penetrate our network security or otherwise misappropriate our customers' personal information or credit card information, or if we give third parties improper access to our customers' personal information or credit card information, we could be subject to liability. This liability could include claims for unauthorized purchases with credit card information, impersonation or other similar fraud claims. This liability could also include claims for other misuses of personal information, including unauthorized marketing purposes. These claims could result in litigation. Liability for misappropriation of this information could adversely affect our business. In addition, the Federal Trade Commission and state agencies have been investigating various Internet companies regarding their use of personal information. We could incur additional expenses if new regulations regarding the use of personal information are introduced or if government agencies investigate our privacy practices.

        We rely on encryption and authentication technology licensed from third parties to provide the security and authentication necessary to effect secure transmission of confidential information such as customer credit card numbers. We cannot assure you that advances in computer capabilities, new discoveries in the field of cryptography or other events or developments will not result in a compromise or breach of the algorithms that we use to protect customer transaction data. If any such compromise of our security were to occur, it could harm our reputation, business, prospects, financial condition and results of operations. A party who is able to circumvent our security measures could misappropriate proprietary information or cause interruptions in our operations. We may be required to expend significant capital and other resources to protect against such security breaches or to alleviate problems caused by such breaches. We cannot assure you that our security measures will prevent security breaches or that failure to prevent such security breaches will not harm our business, prospects, financial condition and results of operations.

We may be subject to product liability claims that could be costly and time consuming.

        We sell products manufactured for us by third parties, some of which may be defective. If any product that we sell were to cause physical injury or injury to property, the injured party or parties could bring claims against us as the manufacturer and/or retailer of the product. Our insurance coverage may not be adequate to cover every claim that could be asserted. If a successful claim were brought against us in excess of our insurance coverage, it could adversely affect our business. Even unsuccessful claims could result in the expenditure of funds and management time and could have a negative impact on our business.

We may face risks relating to our recent acquisition of Ski West, Inc. and the development of our travel business.

        We acquired all of the capital stock of Ski West, Inc., an on-line travel company, on July 1, 2005 and integrated Ski West with our travel operations to form OTravel.com, Inc (our travel business). There can be no assurance about the future performance of our travel business. We may encounter unforeseen operating or other difficulties. The integration of any acquired business can be difficult, and unforeseen problems can arise. Our travel business operates on a software platform that is different from the ones we use in the rest of our business, and it may be difficult or expensive for us to achieve any necessary or desirable integration. Although we have operated a travel service in the past, the travel business operated by Ski West is substantially greater than the travel business we operated, and will involve new and potentially unforeseen risks, including exposure to seasonal and other fluctuations

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in leisure travel, including disruptions resulting from domestic or international terrorist incidents or expectations or perceptions of leisure travelers regarding the safety and desirability of leisure travel.

We have significant indebtedness.

        In connection with our sale of our 3.75% Convertible Senior Notes (the "Senior Notes") in November 2004, we incurred $120.0 million of indebtedness, due December 1, 2011. Under the repurchase program approved by our Board of Directors in 2005, we retired $33.0 million and $10.0 million of the Senior Notes in June and November 2005 for $27.9 million and $7.7 million in cash, respectively. As a result of the note retirements, we recognized a gain of $6.2 million for the year ended December 31, 2005, net of the associated unamortized discount of $1.2 million. As of December 31, 2005, $77.0 million of the Senior Notes remained outstanding. As a result of this indebtedness, our principal and interest payment obligations increased substantially. The degree to which we are leveraged could materially and adversely affect our ability to obtain additional financing for working capital, acquisitions or other purposes and could make us more vulnerable to industry downturns and competitive pressures. Our ability to meet our debt service obligations is dependent upon our future performance, which will be subject to financial, business and other factors affecting our operations, many of which are beyond our control.

We may be unable to generate sufficient cash flow to satisfy our debt service obligations.

        Our ability to generate cash flow from operations to make interest payments on our debt obligations will depend on our future performance, which will be affected by a range of economic, competitive and business factors. We cannot control many of these factors, including general economic conditions and the health of the internet retail industry. If our operations do not generate sufficient cash flow from operations to satisfy our debt service obligations, we may need to borrow additional funds to make these payments or undertake alternative financing plans, such as refinancing or restructuring our debt, or reducing or delaying capital investments and acquisitions. Additional funds or alternative financing may not be available to us on favorable terms, or at all. Our inability to generate sufficient cash flow from operations or obtain additional funds or alternative financing on acceptable terms could have a material adverse effect on our business, prospects, financial condition and results of operations.

Risks Relating to our Auctions Site Business

Our auctions site is a new business.

        Our auctions site began operation in September 2004. The online auctions business is a new business for us, and we cannot ensure that our expansion into the online auctions business will succeed. Our entry into the online auctions business will require us to devote substantial financial, technical, managerial and other resources to the business. It will also expose us to additional risks, including legal and regulatory risks, and it will require us to compete with established businesses having substantially greater experience in the online auctions business and substantially greater resources than we have.

Our auction business may be subject to a variety of regulatory requirements.

        Many states and other jurisdictions, including Utah, where our company is located, have regulations governing the conduct of traditional "auctions" and the liability of traditional "auctioneers" in conducting auctions. Although the vast majority of these regulations clearly contemplated only traditional auctions, not online auctions, the potential application of these types of regulations to online auction sites is not clear. We are aware that several states and some foreign jurisdictions have attempted to impose such regulations on other companies operating online auction sites or on the users of those sites. In addition, certain states have laws or regulations that do expressly apply to online

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auction site services. Although we do not expect these laws to have a significant effect on our auction site business, we will incur costs in complying with these laws, and we may from time to time be required to make changes in our business that may increase our costs, reduce our revenues, cause us to prohibit the listing of certain items in certain locations, or make other changes that may adversely affect our auctions business.

Current and future laws could affect our auctions business.

        Like our shopping site business, our auction site business is subject to the same laws and regulations that apply to other companies conducting business on and off the Internet. In addition, our auction site business may be affected by other laws and regulations, such as those that expressly apply to online auction site services. Further, because of the wide range of items that users of our auctions service may choose to list on the site, a variety of additional laws and regulations may apply to transactions between users of our site, such as those requiring a license to sell or purchase certain items or mandating particular disclosures in connection with an offer or sale of an item. To the extent that such current or future laws or regulations prevent users from selling items on our auction site, they could harm our business.

Our business may be harmed if our auction site is used for unlawful transactions.

        The law regarding the potential liability of an online auction service for the activities of its users is not clear. We prohibit the listing of numerous categories of items in an effort to reduce the possibility that users of our auction site will engage in an unlawful transaction. However, we cannot assure that users of the site will comply with all laws and regulations applicable to them and their transactions, and we may be subject to allegations of civil or criminal liability for any unlawful activities conducted by them. Any costs we incur as a result of any such allegations, or as a result of actual or alleged unlawful transactions utilizing our site, or in our efforts to prevent any such transactions, may harm our business. In addition, any negative publicity we receive regarding any such transactions or allegations may damage our reputation, our ability to attract new customers to our main shopping site, and the Overstock.com brand name generally.

Fraudulent activities using our auctions site and disputes between users of our auctions site may harm our business.

        We are aware that other companies operating online auction services have periodically received complaints from users alleging that they have not received the purchase price or the goods they expected to receive, and that in some cases users have been arrested and convicted for engaging in fraudulent activities using those companies' auction sites. We may receive similar complaints. We do not have the ability to require users of our services to fulfill their obligations to make payments or to deliver items. We are aware that other companies periodically receive complaints from buyers about the quality of the items they purchase, requests for reimbursement of amounts paid, and communications threatening or commencing legal actions against them. We may receive similar complaints, requests and communications in connection with our auctions site business.

We are subject to risks associated with information transmitted through our service.

        The law relating to the liability of online services companies for information carried on or disseminated through their services is currently unsettled. Claims could be made against online services companies under both U.S. and foreign law for defamation, libel, invasion of privacy, negligence, copyright or trademark infringement, or other theories based on the nature and content of the materials disseminated through their services. We are aware that private lawsuits seeking to impose liability under a number of these theories have been brought against other companies operating auction sites. In addition, domestic and foreign legislation has been proposed that would prohibit or impose

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liability for the transmission over the Internet of certain types of information. Our service permits users to make comments regarding other users. Although all such comments are generated by users and not by us, we are aware that claims of defamation or other injury have been made against other companies operating auction services in the past and could be made in the future against us for comments made by users. Recent court decisions have narrowed the scope of the immunity provided to Internet service providers like us under the Communications Decency Act. This trend, if continued, may increase our potential liability to third parties for the user-provided content on our site.

Difficulties or negative publicity associated with our auctions business could affect our main shopping site business.

        Any significant operational or other difficulties we encounter with our auctions business could damage our reputation, our ability to attract new customers to our main shopping site, and the Overstock.com brand name generally. Negative publicity resulting from actual or alleged fraudulent or deceptive conduct by users of our auctions site could also damage our reputation, our ability to attract new customers to our main shopping site, and the Overstock.com brand name generally.

Risks Relating to the Internet Industry

Our success is tied to the continued use of the Internet and the adequacy of the Internet infrastructure.

        Our future revenues and profits, if any, substantially depend upon the continued widespread use of the Internet as an effective medium of business and communication. Factors which could reduce the widespread use of the Internet include:


Customers may be unwilling to use the Internet to purchase goods.

        Our long-term future depends heavily upon the general public's willingness to use the Internet as a means to purchase goods. E-commerce remains a relatively new concept, and large numbers of customers may not begin or continue to use the Internet to purchase goods. The demand for and acceptance of products sold over the Internet are highly uncertain, and most e-commerce businesses have a short track record. If consumers are unwilling to use the Internet to conduct business, our business may not develop profitably.

The security risks or perception of risks of e-commerce may discourage customers from purchasing goods from us.

        In order for the e-commerce market to develop successfully, we and other market participants must be able to transmit confidential information securely over public networks. Third parties may have the technology or know-how to breach the security of customer transaction data. Any breach could cause customers to lose confidence in the security of our Websites and choose not to purchase from our Websites. If someone is able to circumvent our security measures, he or she could destroy or steal valuable information or disrupt our operations. Concerns about the security and privacy of transactions over the Internet could inhibit the growth of the Internet and e-commerce. Our security measures may not effectively prohibit others from obtaining improper access to our information. Third parties may target our customers directly with fraudulent identity theft schemes designed to appear as legitimate communications from us. Any security breach or fraud perpetrated on our customers could expose us to increased costs and to risks of loss, litigation and liability and could seriously disrupt our operations.

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Credit card fraud could adversely affect our business.

        We do not carry insurance against the risk of credit card fraud, so the failure to adequately control fraudulent credit card transactions could reduce our net revenues and our gross margin. We have implemented technology to help us detect the fraudulent use of credit card information. However, we may in the future suffer losses as a result of orders placed with fraudulent credit card data even though the associated financial institution approved payment of the orders. Under current credit card practices, we may be liable for fraudulent credit card transactions because we do not obtain a cardholder's signature. If we are unable to detect or control credit card fraud, our liability for these transactions could harm our business, results of operation or financial condition.

If one or more states successfully assert that we should collect sales or other taxes on the sale of our merchandise or the merchandise of third parties that we offer for sale on our Websites, our business could be harmed.

        We do not currently collect sales or other similar taxes for physical shipments of goods into states other than Utah and Indiana. One or more local, state or foreign jurisdictions may seek to impose sales tax collection obligations on us and other out-of-state companies that engage in online commerce. Our business could be adversely affected if one or more states or any foreign country successfully asserts that we should collect sales or other taxes on the sale of our merchandise.

Existing or future government regulation could harm our business.

        We are subject to the same federal, state and local laws as other companies conducting business on the Internet. Today there are relatively few laws specifically directed towards conducting business on the Internet. However, due to the increasing popularity and use of the Internet, many laws and regulations relating to the Internet are being debated at the state and federal levels. These laws and regulations could cover issues such as user privacy, freedom of expression, pricing, fraud, quality of products and services, taxation, advertising, intellectual property rights and information security. Applicability to the Internet of existing laws governing issues such as property ownership, copyrights and other intellectual property issues, taxation, libel, obscenity and personal privacy could also harm our business. For example, United States and foreign laws regulate our ability to use customer information and to develop, buy and sell mailing lists. The vast majority of these laws was adopted prior to the advent of the Internet, and do not contemplate or address the unique issues raised thereby. Those laws that do reference the Internet are only beginning to be interpreted by the courts and their applicability and reach are therefore uncertain. These current and future laws and regulations could harm our business, results of operation and financial condition.

Laws or regulations relating to privacy and data protection may adversely affect the growth of our Internet business or our marketing efforts.

        We are subject to increasing regulation at the federal, state and international levels relating to privacy and the use of personal user information. For example, we are subject to various telemarketing laws that regulate the manner in which we may solicit future suppliers and customers. Such regulations, along with increased governmental or private enforcement, may increase the cost of growing our business. In addition, many jurisdictions have laws that limit the uses of personal user information gathered online or offline or require companies to establish privacy policies. The Federal Trade Commission has adopted regulations regarding the collection and use of personal identifying information obtained from children under 13. Proposed legislation in this country and existing laws in foreign countries require companies to establish procedures to notify users of privacy and security policies, obtain consent from users for collection and use of personal information, and/or provide users with the ability to access, correct and delete personal information stored by us. Additional legislation regarding data security and privacy has been proposed in Congress. These data protection regulations

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may restrict our ability to collect demographic and personal information from users, which could be costly or harm our marketing efforts, and could require us to implement new and potentially costly processes, procedures and/or protective measures.

Risks Relating to the Securities Markets and Ownership of Our Securities

The price of our securities may be volatile and you may lose all or a part of your investment.

        Our common stock has been publicly traded only since May 30, 2002. The market price of our common stock has been subject to significant fluctuations since the date of our initial public offering. These fluctuations could continue. It is possible that in some future periods our results of operations may be below the expectations of public market analysts and investors. If this occurs, the market price of our securities may decline. Among the factors that could affect the market price of our securities are as follows:


        In addition, the securities markets have experienced significant price and trading volume fluctuations. These broad market fluctuations may adversely affect the trading price of our securities. In the past, following periods of volatility in the market price of a public company's securities, securities class action litigation has often been instituted against that company. Such litigation could result in substantial cost and a diversion of management's attention and resources.

Our quarterly operating results are volatile and may adversely affect the market price of our securities.

        Our future revenues and operating results are likely to vary significantly from quarter to quarter due to a number of factors, many of which are outside our control, and any of which could harm our business. As a result, we believe that quarterly comparisons of our operating results are not necessarily meaningful and that you should not rely on the results of one quarter as an indication of our future performance. In addition to the other risk factors described in this report, additional factors that have caused and/or could cause our quarterly operating results to fluctuate and in turn affect the market price of our securities include:

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Our operating results may fluctuate depending on the season, and such fluctuations may affect the market price of our securities.

        We have experienced and expect to continue to experience fluctuations in our operating results because of seasonal fluctuations in traditional retail patterns. Sales in the retail and wholesale industry tend to be significantly higher in the fourth calendar quarter of each year than in the preceding three quarters due primarily to increased shopping activity during the holiday season. However, there can be no assurance that our sales in the fourth quarter will exceed those of the preceding quarters or, if the fourth quarter sales do exceed those of the preceding quarters, that we will be able to manage the increased sales effectively. Further, we generally increase our inventories substantially in anticipation of holiday season shopping activity, which has a negative effect on our cash flow. Securities analysts and investors may inaccurately estimate the effects of seasonality on our results of operations in one or more future quarters and, consequently, our operating results may fall below expectations, causing the market price of our securities to decline.

We do not intend to pay dividends on our non-redeemable common stock, and you may lose the entire amount of your investment in our common stock.

        We have never declared or paid any cash dividends on our non-redeemable common stock and do not intend to pay dividends on our non-redeemable common stock for the foreseeable future. We intend to invest our future earnings, if any, to fund our growth. Therefore, you will not receive any funds without selling your shares. We cannot assure that you will receive a positive return on your investment when you sell your shares or that you will not lose the entire amount of your investment.

Our Amended and Restated Certificate of Incorporation, Amended and Restated Bylaws and the Delaware General Corporation Law contain anti-takeover provisions which could discourage or prevent a takeover, even if an acquisition would be beneficial to our stockholders.

        Several provisions of our Amended and Restated Certificate of Incorporation and Amended and Restated Bylaws could discourage potential acquisition proposals and could delay or prevent a change in control of our company even if that change in control would be beneficial to our stockholders. For example, only one-third of our board of directors will be elected at each of our annual meetings of stockholders, which will make it more difficult for a potential acquirer to change the management of our company, even after acquiring a majority of the shares of our common stock. These provisions, which cannot be amended without the approval of two-thirds of our stockholders, could diminish the opportunities for a stockholder to participate in tender offers, including tender offers at a price above the then current market value of our common stock. In addition, our board of directors, without further stockholder approval, may issue preferred stock, with such terms as the board of directors may determine, that could have the effect of delaying or preventing a change in control of our company.

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The issuance of preferred stock could also adversely affect the voting powers of the holders of common stock, including the loss of voting control to others. We are also afforded the protections of Section 203 of the Delaware General Corporation Law, which could delay or prevent a change in control of our company or could impede a merger, consolidation, takeover or other business combination involving our company or discourage a potential acquirer from making a tender offer or otherwise attempting to obtain control of our company.

Issuances of our securities are subject to federal and state securities laws, and certain holders of common stock issued by us may be entitled to rescind their purchases.

        Issuances of securities are subject to federal and state securities laws. From November 1999 through September 2000, we offered and sold common stock to investors in various states. Certain of those offerings may not have complied with various requirements of applicable state securities laws. In such situations a number of remedies may be available to regulatory authorities and the investors who purchased common stock in those offerings, including, without limitation, a right of rescission, civil penalties, seizure of our assets, a restraining order or injunction, and a court order to pay restitution and costs. As a result, certain investors in our common stock may be entitled to return their shares to Overstock.com and receive from us the full price they paid, plus interest, which we estimate to be an aggregate amount of approximately $3.2 million at December 31, 2005.

Potential Stock Manipulation

        We have filed an unfair business practice lawsuit against Gradient Analytics, Rocker Partners, L.P. and others, alleging that the defendants have conspired to denigrate Overstock's business for personal profit, as well as an amended complaint alleging additional causes of action and articulating in greater detail the allegations against the defendants. We believe that the defendants have engaged in unlawful actions and have caused substantial harm to Overstock, and that certain of the defendants have made efforts to drive the market price of Overstock's common stock down. To the extent that the defendants or other persons engage in any such actions or other take any other actions to interfere with or destroy or harm Overstock's existing and/or prospective business relationships with its suppliers, bankers, customers, lenders, investors, prospective investors or others, our business, prospects, financial condition and results of operation may suffer, and the price of our common stock may be more volatile than it might otherwise be and/or may trade at prices below those that might prevail in the absence of any such efforts.

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FORWARD-LOOKING STATEMENTS

        This prospectus supplement and the prospectus contain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. These statements are therefore entitled to the protection of the safe harbor provisions of these laws. These forward-looking statements involve risks and uncertainties, and relate to future events or our future financial or operating performance. These statements include, but are not limited to, statements concerning:

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        Furthermore, in some cases, you can identify forward-looking statements by terminology such as may, will, could, should, expect, plan, intend, anticipate, believe, estimate, predict, potential or continue, the negative of such terms or other comparable terminology. These statements are only predictions. Actual events or results may differ materially. In evaluating these statements, you should specifically consider the risks outlined in this prospectus supplement, including those described under "Risk Factors." These factors may cause our actual results to differ materially from those contemplated by any forward-looking statement. Except as otherwise required by law, we expressly disclaim any obligation to release publicly any update or revisions to any forward-looking statements to reflect any changes in our expectations or any change in events, conditions or circumstances on which any of our forward-looking statements are based. Although we believe that the expectations reflected in the forward-looking statements are reasonable, we cannot guarantee future results, levels of activity, performance or achievements.

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USE OF PROCEEDS

        We will receive net proceeds from this offering of approximately $25 million.

        We intend to use the net proceeds from the sale of common stock offered by this prospectus supplement for general corporate purposes and working capital, including sales and marketing activities and inventory purchases. The amounts we actually expend for working capital and other general corporate purposes will vary significantly depending on a number of factors, including future revenue growth, if any, and the amount of cash that we generate from operations. As a result, we will retain broad discretion over the allocation of the net proceeds of this offering. Pending the uses listed above, we intend to invest the net proceeds of this offering in short-term, interest-bearing, investment-grade securities. We cannot predict whether the proceeds invested will yield a favorable return.

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PRICE RANGE OF COMMON STOCK

        Our common stock is traded on the Nasdaq National Market under the symbol "OSTK." The following table sets forth, for the periods indicated, the high and low closing prices per share for our common stock as reported on the Nasdaq National Market since January 1, 2004.

 
   Common
Stock Price
 
   High
   Low
Year Ended December 31, 2004        
  First Quarter   34.84   16.32
  Second Quarter   40.23   30.65
  Third Quarter   38.27   27.88
  Fourth Quarter   76.05   38.43
Year Ended December 31, 2005        
  First Quarter   65.94   41.75
  Second Quarter   45.31   34.15
  Third Quarter   46.87   36.44
  Fourth Quarter   41.59   28.15
Year Ended December 31, 2006        
  First Quarter   32.46   22.18
  Second Quarter (through April 28, 2006)   29.31   25.88

        As of December 31, 2005, there were approximately 238 holders of record of our common stock. Because many of our shares of common stock are held by brokers and other institutions on behalf of shareholders, we are unable to estimate the total number of shareholders represented by these record holders.

        We have never declared or paid any cash dividends on shares of our non-redeemable common stock. We currently intend to retain our earnings for future growth and do not anticipate paying any cash dividends in the foreseeable future. Any future determination to pay dividends will be at the discretion of our board of directors and will depend on our results of operations, financial conditions, contractual and legal restrictions and other factors the board deems relevant.

        Certain offerings of our common stock may not have complied with various requirements of applicable state and securities laws. As such, certain investors in our common stock may be entitled to return their shares to us and receive back from us the full price they paid, plus interest. Although no investors have attempted to exercise a right of rescission, and although we have never declared or paid any cash dividends on shares of common stock that may be subject to rescission, we have recorded "interest," which may be payable on these securities if the rescission rights are exercised, as a deemed dividend in our financial statements. If an investor does attempt to exercise a right of rescission, the interest attributable to their securities would likely become payable in cash.

        During January 2005, the Board of Directors authorized a stock repurchase program under which the Company originally was authorized to repurchase up to $50.0 million of its common stock through December 31, 2007. On April 26, 2005, the Board of Directors increased the amount of the share repurchase program to $100.0 million. Additionally, on June 14, 2005, the Board of Directors authorized an amendment of the stock repurchase program to include the repurchase of our Senior Notes.

        Under the repurchase program, we repurchased approximately 665,000 shares of our common stock in open market transactions for $24.1 million during the year ended December 31, 2005. In addition, approximately 1.0 million shares of common stock were acquired as a result of the settlement of $41.1 million of structured stock repurchase transactions during the nine months ended

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September 30, 2005. The purchased call options that did not settle in stock settled in cash totaling $7.9 million, which we received in July 2005. We also repurchased Senior Notes having an aggregate principal amount of $43 million. We will not make any additional purchases under this repurchase program.

        We have a 401(k) defined contribution plan which permits participating employees to defer up to a maximum of 25% of their compensation, subject to limitations established by the Internal Revenue Code. Employees who have completed a half-year of service and are 21 years of age or older are qualified to participate in the plan. The Company matches 50% of the first 6% of each participant's contributions to the plan. Participant contributions are immediately vested. Company contributions vest based on the participant's years of service at 20% per year over five years. The Company's matching contribution totaled $99,000, $124,000 and $261,000 during 2003, 2004 and 2005, respectively. In addition, for the 2004 and 2005 years, the board of directors approved a 2% (of salary) profit-share contribution to all employees eligible to participate in the plan.

        The Company's board of directors adopted the Amended and Restated 1999 Stock Option Plan, the 2002 Stock Option Plan and the 2005 Equity Incentive Plan (collectively, the "Plans"), in May 1999, April 2002 and April 2005, respectively. Under these Plans, the Board of Directors may issue incentive stock options to employees and directors of the Company and non-qualified stock options to consultants of the Company, as well as other types of awards under the 2005 Equity Incentive Plan. Options granted under these Plans generally expire at the end of five years and vest in accordance with a vesting schedule determined by the Company's Board of Directors, usually over four years from the grant date. As of the initial public offering, the Amended and Restated 1999 Stock Option Plan was terminated. Future awards will be made under the 2005 Equity Incentive Plan. As of December 31, 2005, 1,100,000 shares were available for future grants under these Plans.

        The following is a summary of stock option activity:

 
   2003
   2004
   2005
 
   Shares
   Weighted
Average
Exercise
Price
   Shares
   Weighted
Average
Exercise
Price
   Shares
   Weighted
Average
Exercise
Price
Outstanding—beginning of year   1,415   $ 5.37   1,780   $ 8.39   1,512   $ 8.39
  Granted at fair value   854     12.77   474     24.14   220     44.44
  Exercised   (197 )   4.69   (468 )   6.75   (298 )   8.56
  Canceled/forfeited   (292 )   9.12   (274 )   13.26   (135 )   24.08
   
       
       
     
Outstanding—end of year   1,780     8.39   1,512     12.90   1,299     18.09
   
       
       
     
Options exercisable at year-end   614     5.44   608     7.51   739     11.33

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PLAN OF DISTRIBUTION

        We are selling the common stock offered under this prospectus supplement directly to a single purchaser in a privately negotiated transaction in which no party is acting as an underwriter. The purchaser has agreed to purchase, and we have agreed to sell, 1,041,667 shares of our common stock at a price of $24.00 per share. The price was determined through negotiation with the purchaser.

        We expect to deliver the shares through our transfer agent on or about May 5, 2006.

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EXPERTS

        The consolidated financial statements of Overstock.com, Inc. as of December 31, 2005 and 2004 and for each of the three years in the period ended December 31, 2005 incorporated by reference in this prospectus supplement and the accompanying prospectus have been so incorporated in reliance on the reports of PricewaterhouseCoopers LLP, independent registered public accountants, given on the authority of said firm as experts in auditing and accounting.


WHERE YOU CAN FIND MORE INFORMATION

        We have filed a registration statement with the SEC under the Securities Act of 1933 that registers the securities offered by this prospectus. The registration statement, including the attached exhibits, contains additional relevant information about us. The rules and regulations of the SEC allows us to omit some information included in the registration statement from this prospectus.

        In addition, we file annual, quarterly and other reports and other information with the SEC. You may read and copy any document we file at the SEC's public reference room at 450 Fifth Street, N.W., Washington, D.C. 20549. Please call the SEC at 1-800-732-0330 for further information on the operation of the SEC's public reference room. Our SEC filings are available on the SEC's web site at http://www.sec.gov. We also make available free of charge on our website, at http://www.overstock.com, all materials that we file electronically with the SEC, including our annual report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, Section 16 reports and amendments to these reports as soon as reasonably practicable after such materials are electronically filed with, or furnished to, the SEC.

        The SEC allows us to "incorporate by reference" the information we file with them, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this prospectus supplement and the accompanying prospectus, and information that we file later with the SEC will automatically update and supersede this information. We incorporate by reference the documents listed below and any future filings we will make with the SEC prior to the termination of the offering under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934:


January 6, 2006   February 7, 2006    
January 13, 2006   February 28, 2006    
January 13, 2006   March 6, 2006    
January 27, 2006   April 4, 2006    
January 31, 2006   April 28, 2006 and    
    May 1, 2006.    

        The reports and other documents that we file after the date of this prospectus supplement and prior to the termination of this offering shall be deemed to be incorporated by reference into this prospectus supplement and the accompanying prospectus and will update, supplement and supersede the information in this prospectus supplement and the accompanying prospectus. We will provide to

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each person, including any beneficial owner to whom a prospectus supplement is delivered, a copy of any or all of the information that has been incorporated by reference in the prospectus supplement but not delivered with the prospectus supplement. We will provide this information upon written or oral request at no cost to the requester. You may request a copy of any of this information by writing us at the following address: Overstock.com, Inc. 6350 South 3000 East, Salt Lake City, Utah 84121, Attention: Investor Relations; or by calling our Investor Relations Department at telephone number (801) 947-3132.

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PROSPECTUS

$500,000,000

Logo

Debt Securities
Common Stock
Preferred Stock
Warrants
Stock Purchase Contracts
Units

        Overstock.com, Inc. may sell from time to time in one or more offerings together or separately:

        The total amount of these securities will have an initial aggregate offering price of up to $500,000,000, or the equivalent amount in other currencies, currency units or composite currencies. Our common stock is quoted on The Nasdaq National Market under the symbol "OSTK."

        We may offer and sell these securities to or through one or more underwriters, dealers and agents, or directly to purchasers, on a continuous or delayed basis.

        This prospectus describes some of the general terms that may apply to these securities and the general manner in which they may be offered. The specific terms of any securities to be offered, and the specific manner in which they may be offered, will be described in supplements to this prospectus. You should read this prospectus and the applicable prospectus supplement carefully before you invest.

        See "Risk Factors" beginning on page 1 to read about factors you should consider before buying our securities.

        Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the accuracy or adequacy of this prospectus. Any representation to the contrary is a criminal offense.

This prospectus is dated April 4, 2005


TABLE OF CONTENTS

 
About This Prospectus

Overstock.com, Inc.

Risk Factors

Forward-Looking Statements

Use of Proceeds

Ratio of Earnings to Fixed Charges

Description of the Debt Securities

Description of Common Stock

Description of Preferred Stock

Description of the Warrants

Description of Stock Purchase Contracts

Description of Units

Legal Ownership of Securities

Plan of Distribution

Validity of the Securities

Experts

Where You Can Find More Information

Documents Incorporated By Reference

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ABOUT THIS PROSPECTUS

        This document is called a prospectus and is part of a registration statement that we have filed with the Securities and Exchange Commission, or the SEC, using a "shelf" registration or continuous offering process. Under this shelf process, we may, from time to time, sell any or all of the securities described in this prospectus in one or more offerings up to a total dollar amount of $500,000,000.

        This prospectus provides you with a general description of the securities we may offer. Each time we sell securities, we will provide a prospectus supplement containing specific information about the terms of the securities we are offering. That prospectus supplement may include a discussion of any additional risk factors or other special considerations that apply to those securities. The prospectus supplement also may add, update or change information in this prospectus. If there is any inconsistency between the information in this prospectus and a prospectus supplement, you should rely on the information in that prospectus supplement.

        The registration statement containing this prospectus, including exhibits to the registration statement, provides additional information about us and the securities offered under this prospectus and any prospectus supplement. We have filed and plan to continue to file other documents with the SEC that contain information about us and our business. Also, we will file legal documents that control the terms of the securities offered by this prospectus as exhibits to reports we file with the SEC. The registration statement and other reports can be read at the SEC's Website or at the SEC's public reference room mentioned under the heading "Where You Can Find More Information."

        You should rely only on the information provided in this prospectus and any applicable prospectus supplement, including the information incorporated by reference. Neither we, nor any underwriters, dealers or agents, have authorized anyone to provide you with different information.

        Unless otherwise mentioned or unless the context requires otherwise, all references in this prospectus to "Overstock.com", the "Company", "we", "us", "our", or similar references mean Overstock.com, Inc. Overstock.com and Overstockb2b.com are registered trademarks, and Worldstock.com. Club O and Club O Gold are trademarks of Overstock.com, Inc. The Overstock.com logo and Worldstock.com logo are also trademarks of Overstock.com, Inc. Other service marks, trademarks and trade names referred to in this prospectus are property of their respective owners.

        Neither this prospectus nor any prospectus supplement shall constitute an offer to sell or a solicitation of an offer to buy offered securities in any jurisdiction in which it is unlawful for such person to make such an offering or solicitation. Neither the delivery of this prospectus or any prospectus supplement nor any sale made hereunder shall under any circumstances imply that the information contained or incorporated by reference herein or in any prospectus supplement is correct as of any date subsequent to the date hereof or of such prospectus supplement.

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OVERSTOCK.COM, INC.

        We are an online "closeout" retailer offering discount, brand-name merchandise for sale primarily over the Internet. Our merchandise offerings include bed-and-bath goods, kitchenware, watches, jewelry, electronics, sporting goods and designer accessories, as well as books, magazines, CDs, DVDs, video cassettes and video games. We offer our customers an opportunity to shop for bargains conveniently, while offering our suppliers an alternative inventory liquidation distribution channel, on our main website, www.overstock.com.

        Our principal executive offices are located at 6322 South 3000 East, Suite 100, Salt Lake City, Utah 84121, and our telephone number is (801) 947-3100. We were formed in 1997, and completed our initial public offering in June 2002. Our main Website address is www.overstock.com. The information contained on our Websites is not part of this prospectus.


RISK FACTORS

        Any investment in our securities involves a high degree of risk. You should consider carefully the risks and uncertainties described below, and all other information contained in or incorporated by reference into this prospectus, before you decide whether to purchase our securities. Additional risks and uncertainties not currently known to us or that we currently deem immaterial may also become important factors that may harm our business. The occurrence of any of the following risks could harm our business. The trading price of our securities could decline due to any of these risks and uncertainties, and you may lose part or all of your investment.

Risks Relating to Overstock.com

        We have a history of significant losses. If we do not achieve profitability, our financial condition and our stock price could suffer.

        We have a history of losses and we may continue to incur operating and net losses for the foreseeable future. We incurred net losses attributable to common shares of $5.2 million and $12.1 million for the years ended December 31, 2004 and 2003, respectively. As of December 31, 2004 and 2003, our accumulated deficit was $73.0 million and $67.8 million, respectively. We will need to generate significant revenues to achieve profitability, and we may not be able to do so. Even if we do achieve profitability, we may not be able to sustain or increase profitability on a quarterly or annual basis in the future. If our revenues grow more slowly than we anticipate, or if our operating expenses exceed our expectations, our financial results would be severely harmed.

        We will continue to incur significant operating expenses and may continue to incur operating and net losses for the foreseeable future. Because we will incur many of these expenses before we receive any revenues from our efforts, our losses may be greater than the losses we would incur if we developed our business more slowly. Further, we base our expenses in large part on our operating plans and future revenue projections. Many of our expenses are fixed in the short term, and we may not be able to quickly reduce spending if our revenues are lower than we project. Therefore, any significant shortfall in revenues would likely harm our business, operating results and financial condition. In addition, we may find that these efforts are more expensive than we currently anticipate, which would further increase our losses. Also, the timing of these expenses may contribute to fluctuations in our quarterly operating results.

        If we fail to accurately forecast our expenses and revenues, our business, operating results and financial condition may suffer and the price of our stock may decline.

        Our limited operating history and the rapidly evolving nature of our industry make forecasting quarterly operating results difficult. We may not be able to quickly reduce spending if our revenues are

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lower than we project. Therefore, any significant shortfall in revenues would likely harm our business, operating results and financial condition and cause our results of operation to fall below the expectations of public market analysts and investors. If this occurs, the price of our common stock may decline.

        We depend on our relationships with third-party fulfillment partners for a large portion of the products that we offer for sale on our Websites. If we fail to maintain these relationships, our business will suffer.

        During the quarter ended December 31, 2004, we had active fulfillment partner relationships with approximately 400 third parties whose products we offer for sale on our Websites. At December 31, 2004, these products accounted for approximately 77% of the non-BMV products available on our Websites. We do not have any long-term agreements with any of these third parties. Our agreements with third parties are terminable at will by either party immediately upon notice. In general, we agree to offer the third parties' products on our Websites and these third parties agree to provide us with information about their products, honor our customer service policies and ship the products directly to the customer. If we do not maintain our existing or build new relationships with third parties on acceptable commercial terms, we may not be able to offer a broad selection of merchandise, and customers may not shop at our Websites. In addition, manufacturers may decide not to offer particular products for sale on the Internet. If we are unable to maintain our existing or build new fulfillment partner relationships or if other product manufacturers refuse to allow their products to be sold via the Internet, our business would suffer severely.

        We are partially dependent on third parties to fulfill a number of our fulfillment, distribution and other retail functions. If such parties are unwilling or unable to continue providing these services, our business could be seriously harmed.

        In our fulfillment partner business, although we now handle returned merchandise, we continue to rely on third parties to conduct a number of other traditional retail operations with respect to their respective products that we offer for sale on our Websites, including maintaining inventory, preparing merchandise for shipment to individual customers and timely distribution of purchased merchandise. We have no effective means to ensure that these third parties will continue to perform these services to our satisfaction or on commercially reasonable terms. In addition, because we do not take possession of these third parties' products, we are unable to fulfill these traditional retail operations ourselves. Our customers could become dissatisfied and cancel their orders or decline to make future purchases if these third parties are unable to deliver products on a timely basis. If our customers become dissatisfied with the services provided by these third parties, our reputation and the Overstock.com brand could suffer.

        We rely on our relationships with manufacturers, retailers and other suppliers to obtain sufficient quantities of quality merchandise on acceptable terms. If we fail to maintain our supplier relationships on acceptable terms, our sales and profitability could suffer.

        To date, we have not entered into contracts with manufacturers or liquidation wholesalers that guarantee the availability of merchandise for a set duration. Our contracts or arrangements with suppliers do not provide for the continuation of particular pricing practices and may be terminated by either party at any time. Our current suppliers may not continue to sell their excess inventory to us on current terms or at all, and we may not be able to establish new supply relationships. For example, it is difficult for us to maintain high levels of product quality and selection because none of the manufacturers, suppliers and liquidation wholesalers from whom we purchase products on a purchase order by purchase order basis have a continuing obligation to provide us with merchandise at historical levels or at all. In most cases, our relationships with our suppliers do not restrict the suppliers from selling their respective excess inventory to other traditional or online merchandise liquidators, which

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could in turn limit the selection of products available on our Websites. If we are unable to develop and maintain relationships with suppliers that will allow us to obtain sufficient quantities of merchandise on acceptable commercial terms, such inability could harm our business, results of operation and financial condition.

        We depend upon third-party delivery services to deliver our products to our customers on a timely and consistent basis. A deterioration in our relationship with any one of these third parties could decrease our ability to track shipments, cause shipment delays, and increase our shipping costs and the number of damaged products.

        We rely upon multiple third parties for the shipment of our products. Because we do not have a written long-term agreement with any of these third parties, we cannot be sure that these relationships will continue on terms favorable to us, if at all. Unexpected increases in shipping costs or delivery times, particularly during the holiday season, could harm our business, prospects, financial condition and results of operations. If our relationships with these third parties are terminated or impaired or if these third parties are unable to deliver products for us, whether through labor shortage, slow down or stoppage, deteriorating financial or business condition, responses to terrorist attacks or for any other reason, we would be required to use alternative carriers for the shipment of products to our customers. We may be unable to engage alternative carriers on a timely basis or upon terms favorable to us. Changing carriers would likely have a negative effect on our business, operating results and financial condition. Potential adverse consequences include:

        A significant number of merchandise returns could harm our business, financial condition and results of operations.

        We allow our customers to return products and beginning July 1, 2003, we started accepting returns of products sold through our fulfillment partners. Our ability to handle a large volume of returns is unproven. In addition, any policies intended to reduce the number of product returns may result in customer dissatisfaction and fewer return customers. If merchandise returns are significant, our business, financial condition and results of operations could be harmed.

        If the products that we offer on our Websites do not reflect our customers' tastes and preferences, our sales and profit margins would decrease.

        Our success depends in part on our ability to offer products that reflect consumers' tastes and preferences. Consumers' tastes are subject to frequent, significant and sometimes unpredictable changes. Because the products that we sell typically consist of manufacturers' and retailers' excess inventory, we have limited control over the specific products that we are able to offer for sale. If our merchandise fails to satisfy customers' tastes or respond to changes in customer preferences, our sales could suffer and we could be required to mark down unsold inventory which would depress our profit margins. In addition, any failure to offer products in line with customers' preferences could allow our competitors to gain market share. This could have an adverse effect on our business, results of operations and financial condition.

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        We face risks relating to our inventory.

        We directly purchase some of the merchandise that we sell on our Websites. We assume the inventory damage, theft and obsolescence risks, as well as price erosion risks for products that we purchase directly. These risks are especially significant because some of the merchandise we sell at our Websites are characterized by rapid technological change, obsolescence and price erosion (for example, computer hardware, software and consumer electronics), and because we sometimes make large purchases of particular types of inventory. In addition, we often do not receive warranties on the merchandise we purchase. Further, beginning July 1, 2003, we started accepting returns of products sold through our fulfillment partners, and we have the risk of reselling the returned products.

        In the recent past, we have recorded charges for obsolete inventory and have had to sell certain merchandise at a discount or loss. It is impossible to determine with certainty whether an item will sell for more than the price we pay for it. Because we rely heavily on purchased inventory, our success will depend on our ability to liquidate our inventory rapidly, the ability of our buying staff to purchase inventory at attractive prices relative to its resale value and our ability to manage customer returns and the shrinkage resulting from theft, loss and misrecording of inventory. If we are unsuccessful in any of these areas, we may be forced to sell our inventory at a discount or loss.

        We have grown quickly and if we fail to manage our growth, our business will suffer.

        We have rapidly and significantly expanded our operations, and anticipate that further significant expansion will be required to address potential growth in our customer base and market opportunities. This expansion has placed, and is expected to continue to place, a significant strain on our management, operational and financial resources. Some of our officers have no prior senior management experience at public companies. Our new employees include a number of key managerial, technical and operations personnel who have not yet been fully integrated into our operations, and we expect to add additional key personnel in the future. To manage the expected growth of our operations and personnel, we will be required to improve existing and implement new transaction-processing, operational and financial systems, procedures and controls, and to expand, train and manage our already growing employee base. If we are unable to manage growth effectively, our business, prospects, financial condition and results of operations will be harmed.

        The loss of key personnel or any inability to attract and retain additional personnel could affect our ability to successfully grow our business.

        Our performance is substantially dependent on the continued services and on the performance of our senior management and other key personnel, particularly Patrick M. Byrne, our President and Chairman of the Board. Our performance also depends on our ability to retain and motivate other officers and key employees. The loss of the services of any of our executive officers or other key employees for any unforeseen reason, including without limitation, illness or call to military service, could harm our business, prospects, financial condition and results of operations. We do not have employment agreements with any of our key personnel and we do not maintain "key person" life insurance policies. Our future success also depends on our ability to identify, attract, hire, train, retain and motivate other highly-skilled technical, managerial, editorial, merchandising, marketing and customer service personnel. Competition for such personnel is intense, and we cannot assure you that we will be able to successfully attract, assimilate or retain sufficiently qualified personnel. Our failure to retain and attract the necessary technical, managerial, editorial, merchandising, marketing and customer service personnel could harm our revenues, business, prospects, financial condition and results of operations.

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        We may be unable to manage expansion into new business areas which could harm our business operations and reputation.

        Our long-term strategic plan involves expansion of our operations in the liquidation market, entering into agreements to provide products and services to retail chains and other businesses, and possible expansion into additional markets. We cannot assure you that our efforts to expand our business in this manner will succeed or that we will be successful in managing or maintaining agreements to provide products and services to retail chains and other businesses. We were unable to generate significant traffic for our former B2B Website, and consequently we merged our B2B site (www.overstockb2b.com) into our B2C site, and opened a "Club O Gold" bulk purchase program (into which our current B2B customers were grandfathered). Our failure to succeed in this market or other markets may harm our business, prospects, financial condition and results of operation. We cannot assure you that we would be able to expand our efforts and operations in a cost-effective or timely manner or that any such efforts would increase overall market acceptance. Furthermore, any new business or Website we launch that is not favorably received by consumers could damage our reputation or the Overstock.com brand. We may expand the number of categories of products we carry on our Website. These and any other expansions of our operations would also require significant additional expenses and development and would strain our management, financial and operational resources. The lack of market acceptance of such efforts or our inability to generate satisfactory revenues from such expanded services or products to offset their cost could harm our business, prospects, financial condition and results of operations.

        We may expand our international business, causing our business to become increasingly susceptible to numerous international business risks and challenges that could affect our profitability.

        We have begun to expand into international markets, and in the future we may do so more aggressively. International sales and transactions are subject to inherent risks and challenges that could adversely affect our profitability, including:


        To the extent we generate international sales and transactions in the future, any negative impact on our international operations could negatively impact our business. In particular, gains and losses on the conversion of foreign payments into United States dollars may contribute to fluctuations in our results of operations and fluctuating exchange rates could cause reduced gross revenues and/or gross margins from non-dollar-denominated international sales.

        In order to obtain future revenue growth and achieve and sustain profitability we will have to attract customers on cost-effective terms.

        Our success depends on our ability to attract customers on cost-effective terms. We have relationships with online services, search engines, directories and other Websites and e-commerce businesses to provide content, advertising banners and other links that direct customers to our

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Websites. We rely on these relationships as significant sources of traffic to our Websites and to generate new customers. If we are unable to develop or maintain these relationships on acceptable terms, our ability to attract new customers and our financial condition could be harmed. In addition, certain of our online marketing agreements may require us to pay upfront fees and make other payments prior to the realization of the sales, if any, associated with those payments. Accordingly, if these agreements or similar agreements that we may enter into in the future fail to produce the sales that we anticipate, our results of operations will be adversely affected. We cannot assure you that we will be able to increase our revenues, if at all, in a cost-effective manner. We have also begun national television and radio branding and advertising campaigns. Such campaigns are expensive and may not result in the cost effective acquisition of customers.

        Further, many of the parties with which we may have online-advertising arrangements could provide advertising services for other online or traditional retailers and merchandise liquidators. As a result, these parties may be reluctant to enter into or maintain relationships with us. Failure to achieve sufficient traffic or generate sufficient revenue from purchases originating from third parties may result in termination of these relationships by these third parties. Without these relationships, our revenues, business, prospects, financial condition and results of operations could suffer.

        We may not be able to compete successfully against existing or future competitors.

        The online liquidation services market is new, rapidly evolving and intensely competitive. Barriers to entry are minimal, and current and new competitors can launch new Websites at a relatively low cost. Our consumer Website currently competes with:

        Our Website competes with liquidation "brokers" and retailers and online marketplaces such as eBay, Inc.

        We expect the online liquidation services market to become even more competitive as traditional liquidators and online retailers continue to develop services that compete with our services. In addition, manufacturers and retailers may decide to create their own Websites to sell their own excess inventory and the excess inventory of third parties. Competitive pressures created by any one of our competitors, or by our competitors collectively, could severely harm our business, prospects, financial condition and results of operations.

        Further, as a strategic response to changes in the competitive environment, we may from time to time make certain pricing, service or marketing decisions or acquisitions that could harm our business, prospects, financial condition and results of operations. For example, to the extent that we enter new lines of businesses such as third-party logistics or discount brick and mortar retail, we would be competing with large established businesses such as APL Logistics, Ltd., Ross Stores, Inc. and TJX Companies, Inc., respectively. We have recently entered the online auctions business, in which we compete with large established businesses including eBay, Inc.

        Many of our current and potential competitors described above have longer operating histories, larger customer bases, greater brand recognition and significantly greater financial, marketing and other resources than we do. In addition, online retailers and liquidation e-tailers may be acquired by, receive investments from or enter into other commercial relationships with larger, well-established and well-financed companies. Some of our competitors may be able to secure merchandise from

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manufacturers on more favorable terms, devote greater resources to marketing and promotional campaigns, adopt more aggressive pricing or inventory availability policies and devote substantially more resources to Website and systems development than we do. Increased competition may result in reduced operating margins, loss of market share and a diminished brand franchise. We cannot assure you that we will be able to compete successfully against current and future competitors.

        Our operating results depend on our Websites, network infrastructure and transaction-processing systems. Capacity constraints or system failures would harm our business, prospects, results of operations and financial condition.

        Any system interruptions that result in the unavailability of our Websites or reduced performance of our transaction systems would reduce our transaction volume and the attractiveness of the services that we provide to suppliers and third parties and would seriously harm our business, operating results and financial condition.

        We use internally developed systems for our Websites and certain aspects of transaction processing, including customer profiling and order verifications. We have experienced periodic systems interruptions due to server failure, which we believe will continue to occur from time to time. If the volume of traffic on our Websites or the number of purchases made by customers substantially increases, we will need to further expand and upgrade our technology, transaction processing systems and network infrastructure. We have experienced and expect to continue to experience temporary capacity constraints due to sharply increased traffic during sales or other promotions, and during the holiday shopping season. Capacity constraints can cause unanticipated system disruptions, slower response times, degradation in levels of customer service, impaired quality and delays in reporting accurate financial information.

        Our transaction processing systems and network infrastructure may be unable to accommodate increases in traffic in the future. We may be unable to project accurately the rate or timing of traffic increases or successfully upgrade our systems and infrastructure to accommodate future traffic levels on our Websites. In addition, we may be unable to upgrade and expand our transaction processing systems in an effective and timely manner or to integrate any newly developed or purchased functionality with our existing systems. Any inability to do so may cause unanticipated system disruptions, slower response times, degradation in levels of customer service, impaired quality and speed of order fulfillment or delays in reporting accurate financial information.

        If the facilities where substantially all of our computer and communications hardware is located fail, our business, results of operations and financial condition will be harmed.

        Our success, and, in particular, our ability to successfully receive and fulfill orders and provide high-quality customer service, largely depends on the efficient and uninterrupted operation of our computer and communications hardware systems. Substantially all of our computer and communications hardware is located at a single co-location facility in Salt Lake City, Utah, with a backup system located at another leased facility in Salt Lake City, Utah. Although we have designed our backup system in an effort to avoid or minimize service interruptions in the event of a failure of our main facility, our systems and operations are vulnerable to damage or interruption from fire, flood, power loss, telecommunications failure, terrorist attacks, acts of war, break-ins, earthquake and similar events. We do not have a formal disaster recovery plan and our business interruption insurance may be insufficient to compensate us for losses that may occur. Despite the implementation of network security measures, our servers are vulnerable to computer viruses, physical or electronic break-ins and similar disruptions, which could lead to interruptions, delays, loss of critical data or the inability to accept and fulfill customer orders. The occurrence of any of the foregoing risks could harm our business, prospects, financial condition and results of operations.

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        We may be unable to protect our proprietary technology or keep up with that of our competitors.

        Our success depends to a significant degree upon the protection of our software and other proprietary intellectual property rights. We may be unable to deter misappropriation of our proprietary information, detect unauthorized use and take appropriate steps to enforce our intellectual property rights. In addition, our competitors could, without violating our proprietary rights, develop technologies that are as good as or better than our technology.

        Our failure to protect our software and other proprietary intellectual property rights or to develop technologies that are as good as our competitors' could put us at a disadvantage to our competitors. In addition, the failure of the third parties whose products we offer for sale on our Websites to protect their intellectual property rights, including their domain names, could impair our operations. These failures could harm our business, results of operations and financial condition.

        If we do not respond to rapid technological changes, our services could become obsolete and we could lose customers.

        To remain competitive, we must continue to enhance and improve the functionality and features of our e-commerce businesses. We may face material delays in introducing new services, products and enhancements. If this happens, our customers may forgo the use of our Websites and use those of our competitors. The Internet and the online commerce industry are rapidly changing. If competitors introduce new products and services using new technologies or if new industry standards and practices emerge, our existing Websites and our proprietary technology and systems may become obsolete. Our failure to respond to technological change or to adequately maintain, upgrade and develop our computer network and the systems used to process customers' orders and payments could harm our business, prospects, financial condition and results of operations.

        We may not be able to obtain trademark protection for our marks, which could impede our efforts to build brand identity.

        We have filed trademark applications with the Patent and Trademark Office seeking registration of certain service marks or trademarks. There can be no assurance that our applications will be successful or that we will be able to secure significant protection for our service marks or trademarks in the United States or elsewhere as we expand internationally. Our competitors or others could adopt product or service marks similar to our marks, or try to prevent us from using our marks, thereby impeding our ability to build brand identity and possibly leading to customer confusion. Any claim by another party against us or customer confusion related to our trademarks, or our failure to obtain trademark registration, could negatively affect our business.

        We may not be able to enforce protection of our intellectual property rights under the laws of other countries.

        As we continue to expand internationally, we are subject to risks of doing business internationally as related to our intellectual property, including:

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        Our business and reputation may be harmed by the listing or sale of pirated, counterfeit or illegal items by third parties, and by intellectual property litigation.

        We have received in the past, and we anticipate we will receive in the future, communications alleging that certain items listed or sold through our Websites infringe third-party copyrights, trademarks and trade names or other intellectual property rights or that we have otherwise infringed third parties' past, current or future intellectual property rights. For example, in October 2003, Tiffany (NJ) Inc. and Tiffany and Company filed a complaint against us in the United States District Court for the Southern District of New York alleging that we have distributed counterfeit and otherwise unauthorized Tiffany product in violation of federal copyright and trademark law and related state laws. In addition, in January 2005, Tiffany filed additional complaints against us asserting similar claims.

        We may be unable to prevent third parties from listing unlawful goods, and we may be subject to allegations of civil or criminal liability for unlawful activities carried out by third parties through our Websites. In the future, we may implement measures to protect against these potential liabilities that could require us to spend substantial resources and/or to reduce revenues by discontinuing certain service offerings. Any costs incurred as a result of liability or asserted liability relating to the sale of unlawful goods or the unlawful sale of goods could harm our revenues, business, prospects, financial condition and results of operations.

        Resolving litigation or claims regarding patents or other intellectual property, whether meritorious or not, could be costly, time-consuming, cause service delays, divert our management and key personnel from our business operations, require expensive or unwanted changes in our methods of doing business or require us to enter into costly royalty or licensing agreements, if available. As a result, these claims could harm our business.

        Negative publicity generated as a result of the foregoing could damage our reputation, harm our business and diminish the value of our brand name.

        We may be liable if third parties misappropriate our customers' personal information.

        If third parties are able to penetrate our network security or otherwise misappropriate our customers' personal information or credit card information, or if we give third parties improper access to our customers' personal information or credit card information, we could be subject to liability. This liability could include claims for unauthorized purchases with credit card information, impersonation or other similar fraud claims. This liability could also include claims for other misuses of personal information, including unauthorized marketing purposes. These claims could result in litigation. Liability for misappropriation of this information could adversely affect our business. In addition, the Federal Trade Commission and state agencies have been investigating various Internet companies regarding their use of personal information. We could incur additional expenses if new regulations regarding the use of personal information are introduced or if government agencies investigate our privacy practices.

        We rely on encryption and authentication technology licensed from third parties to provide the security and authentication necessary to effect secure transmission of confidential information such as customer credit card numbers. We cannot assure you that advances in computer capabilities, new discoveries in the field of cryptography or other events or developments will not result in a compromise or breach of the algorithms that we use to protect customer transaction data. If any such compromise of our security were to occur, it could harm our reputation, business, prospects, financial condition and results of operations. A party who is able to circumvent our security measures could misappropriate proprietary information or cause interruptions in our operations. We may be required to expend significant capital and other resources to protect against such security breaches or to alleviate problems caused by such breaches. We cannot assure you that our security measures will prevent security

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breaches or that failure to prevent such security breaches will not harm our business, prospects, financial condition and results of operations.

        We may be subject to product liability claims that could be costly and time consuming.

        We sell products manufactured by third parties, some of which may be defective. If any product that we sell were to cause physical injury or injury to property, the injured party or parties could bring claims against us as the retailer of the product. Our insurance coverage may not be adequate to cover every claim that could be asserted. If a successful claim were brought against us in excess of our insurance coverage, it could adversely affect our business. Even unsuccessful claims could result in the expenditure of funds and management time and could have a negative impact on our business.

        We have significant indebtedness.

        In connection with our sale of our 3.75% Convertible Senior Notes (the "notes") in November 2004, we incurred $120,000,000 of indebtedness. As a result of this indebtedness, our principal and interest payment obligations increased substantially. The degree to which we will be leveraged could materially and adversely affect our ability to obtain additional financing for working capital, acquisitions or other purposes and could make us more vulnerable to industry downturns and competitive pressures. Our ability to meet our debt service obligations will be dependent upon our future performance, which will be subject to financial, business and other factors affecting our operations, many of which are beyond our control.

        We may be unable to generate sufficient cash flow to satisfy our debt service obligations.

        Our ability to generate cash flow from operations to make interest payments on our debt obligations will depend on our future performance, which will be affected by a range of economic, competitive and business factors. We cannot control many of these factors, including general economic conditions and the health of the internet retail industry. If our operations do not generate sufficient cash flow from operations to satisfy our debt service obligations, we may need to borrow additional funds to make these payments or undertake alternative financing plans, such as refinancing or restructuring our debt, or reducing or delaying capital investments and acquisitions. Additional funds or alternative financing may not be available to us on favorable terms, or at all. Our inability to generate sufficient cash flow from operations or obtain additional funds or alternative financing on acceptable terms could have a material adverse effect on our business, financial condition and results of operations.

        Issuances of our securities are subject to federal and state securities laws, and certain holders of common stock issued by us may be entitled to rescind their purchases.

        Issuances of securities are subject to federal and state securities laws. From November 1999 through September 2000, we offered and sold common stock to investors in various states. Certain of those offerings may not have complied with various requirements of applicable state securities laws. In such situations a number of remedies may be available to regulatory authorities and the investors who purchased common stock in those offerings, including, without limitation, a right of rescission, civil penalties, seizure of our assets, a restraining order or injunction, and a court order to pay restitution and costs. As a result, certain investors in our common stock may be entitled to return their shares to Overstock.com and receive from us the full price they paid, plus interest, which we estimate to be an aggregate amount of approximately $3.2 million at December 31, 2004.

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Risks Relating to our Auctions Site Business

        Our auctions site is a new business.

        Our auctions site began operation in September 2004. The online auctions business is a new business for us, and we cannot assure you that our expansion into the online auctions business will succeed. Our entry into the online auctions business will require us to devote substantial financial, technical, managerial and other resources to the business. It will also expose us to additional risks, including legal and regulatory risks, and will require us to compete with established businesses having substantially greater experience in the online auctions business and substantially greater resources than we do.

        Our auction business may be subject to a variety of regulatory requirements.

        Many states and other jurisdictions, including Utah, where our company is located, have regulations governing the conduct of traditional "auctions" and the liability of traditional "auctioneers" in conducting auctions. Although the vast majority of these regulations clearly contemplated only traditional auctions, and did not contemplate online auctions, the potential application of these types of regulations to online auction sites is not clear. We are aware that several states and some foreign jurisdictions have attempted to impose such regulations on other companies operating online auction sites or on the users of those sites. In addition, certain states have laws or regulations that do expressly apply to online auction site services. Although we do not expect these laws to have a significant effect on our auction site business, we will incur costs in complying with these laws, and we may from time to time be required to make changes in our business that may increase our costs, reduce our revenues, cause us to prohibit the listing of certain items in certain locations, or make other changes that may adversely affect our auctions business.

        Current and future laws could affect our auctions business.

        Like our shopping site business, our auction site business is subject to the same laws and regulations as apply to other companies conducting business on and off the Internet. In addition, our auction site business may be affected by other laws and regulations, such as those that expressly apply to online auction site services. Further, because of the wide range of items that users of our auctions service may choose to list on the site, a variety of additional laws and regulations may apply to transactions between users of our site, such as those requiring a license to sell or purchase certain items or mandating particular disclosures in connection with an offer or sale of an item. To the extent that such current or future laws or regulations prevent users from selling items on our auction site, they could harm our business.

        Our business may be harmed if our auction site is used for unlawful transactions.

        The law regarding the potential liability of an online auction service for the activities of its users is not clear. We prohibit the listing of numerous categories of items in an effort to reduce the possibility that users of our auction site will engage in an unlawful transaction. However, we cannot assure that users of the site will comply with all laws and regulations applicable to them and their transactions, and we may be subject to allegations of civil or criminal liability for any unlawful activities conducted by them. Any costs we incur as a result of any such allegations, or as a result of actual or alleged unlawful transactions utilizing our site, or in our efforts to prevent any such transactions, may harm our business. In addition, any negative publicity we receive regarding any such transactions or allegations may damage our reputation, our ability to attract new customers to our main shopping site, and the Overstock.com brand name generally.

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        Fraudulent activities using our auctions site and disputes between users of our auctions site may harm our business.

        We are aware that other companies operating online auction services have periodically received complaints from users alleging that they have not received the purchase price or the goods they expected to receive, and that in some cases users have been arrested and convicted for engaging in fraudulent activities using those companies' auction sites. We may receive similar complaints. We do not have the ability to require users of our services to fulfill their obligations to make payments or to deliver items. We are aware that other companies periodically receive complaints from buyers about the quality of the items they purchase, requests for reimbursement of amounts paid, and communications threatening or commencing legal actions against them. We may receive similar complaints, requests and communications in connection with our auctions site business.

        Difficulties or negative publicity associated with our auctions business could affect our main shopping site business.

        Any significant operational or other difficulties we encounter with our auctions business could damage our reputation, our ability to attract new customers to our main shopping site, and the Overstock.com brand name generally. Negative publicity resulting from actual or alleged fraudulent or deceptive conduct by users of our auctions site could also damage our reputation, our ability to attract new customers to our main shopping site, and the Overstock.com brand name generally.

Risks Relating to the Internet Industry and Regulatory Matters

        Our success is tied to the continued use of the Internet and the adequacy of the Internet infrastructure.

        Our future revenues and profits, if any, substantially depend upon the continued widespread use of the Internet as an effective medium of business and communication. Factors which could reduce the widespread use of the Internet include:


        Customers may be unwilling to use the Internet to purchase goods.

        Our long-term future depends heavily upon the general public's willingness to use the Internet as a means to purchase goods. E-commerce remains a relatively new concept, and large numbers of customers may not begin or continue to use the Internet to purchase goods. The demand for and acceptance of products sold over the Internet are highly uncertain, and most e-commerce businesses have a short track record. If consumers are unwilling to use the Internet to conduct business, our business may not develop profitably.

        The security risks of e-commerce may discourage customers from purchasing goods from us.

        In order for the e-commerce market to develop successfully, we and other market participants must be able to transmit confidential information securely over public networks. Third parties may have the technology or know-how to breach the security of customer transaction data. Any breach could cause customers to lose confidence in the security of our Websites and choose not to purchase from our Websites. If someone is able to circumvent our security measures, he or she could destroy or steal valuable information or disrupt our operations. Concerns about the security and privacy of transactions over the Internet could inhibit the growth of the Internet and e-commerce. Our security measures may

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not effectively prohibit others from obtaining improper access to our information. Third parties may target our customers directly with fraudulent identity theft schemes designed to appear as legitimate communications from us. Any security breach or fraud perpetrated on our customers could expose us to increased costs and to risks of loss, litigation and liability and could seriously disrupt our operations.

        Credit card fraud could adversely affect our business.

        We do not carry insurance against the risk of credit card fraud, so the failure to adequately control fraudulent credit card transactions could reduce our net revenues and our gross margin. We have implemented technology to help us detect the fraudulent use of credit card information. However, we may in the future suffer losses as a result of orders placed with fraudulent credit card data even though the associated financial institution approved payment of the orders. Under current credit card practices, we may be liable for fraudulent credit card transactions because we do not obtain a cardholder's signature. If we are unable to detect or control credit card fraud, our liability for these transactions could harm our business, results of operation or financial condition.

        If one or more states successfully assert that we should collect sales or other taxes on the sale of our merchandise or the merchandise of third parties that we offer for sale on our Websites, our business could be harmed.

        We do not currently collect sales or other similar taxes for physical shipments of goods into states other than Utah. One or more local, state or foreign jurisdictions may seek to impose sales tax collection obligations on us and other out-of-state companies that engage in online commerce. Our business could be adversely affected if one or more states or any foreign country successfully asserts that we should collect sales or other taxes on the sale of our merchandise.

        Existing or future government regulation could harm our business.

        We are subject to the same federal, state and local laws as other companies conducting business on the Internet. Today there are relatively few laws specifically directed towards conducting business on the Internet. However, due to the increasing popularity and use of the Internet, many laws and regulations relating to the Internet are being debated at the state and federal levels. These laws and regulations could cover issues such as user privacy, freedom of expression, pricing, fraud, quality of products and services, taxation, advertising, intellectual property rights and information security. Applicability to the Internet of existing laws governing issues such as property ownership, copyrights and other intellectual property issues, taxation, libel, obscenity and personal privacy could also harm our business. For example, United States and foreign laws regulate our ability to use customer information and to develop, buy and sell mailing lists. The vast majority of these laws were adopted prior to the advent of the Internet, and do not contemplate or address the unique issues raised thereby. Those laws that do reference the Internet, such as the Digital Millennium Copyright Act and the CAN-SPAM Act of 2003, are only beginning to be interpreted by the courts and their applicability and reach are therefore uncertain. These current and future laws and regulations could harm our business, results of operation and financial condition. We have recently received an inquiry from the Federal Trade Commission regarding our compliance with the FTC's Mail or Telephone Order Merchandise Trade Regulation Rule and Section 5 of the FTC Act. Although we are cooperating fully with the FTC's inquiry, we are in the preliminary stage of responding to the inquiry, and at present are unable to predict the outcome of the inquiry.

        We may be materially affected by regulatory requirements.

        We are subject to various other regulatory requirements, including the Sarbanes-Oxley Act of 2002. Section 404 of the Sarbanes-Oxley Act requires that we evaluate and determine the effectiveness of our internal control over financial reporting. If we or our independent registered public accounting firm

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determine that we have a material weakness in our internal control over financial reporting, we could incur additional costs and suffer adverse publicity and other consequences of any such determination.

        Laws or regulations relating to privacy and data protection may adversely affect the growth of our Internet business or our marketing efforts.

        We are subject to increasing regulation at the federal, state and international levels relating to privacy and the use of personal user information. For example, we are subject to various telemarketing laws that regulate the manner in which we may solicit future suppliers and customers. Such regulations, along with increased governmental or private enforcement, may increase the cost of growing our business. In addition, several states have proposed legislation that would limit the uses of personal user information gathered online or require online services to establish privacy policies. The Federal Trade Commission has adopted regulations regarding the collection and use of personal identifying information obtained from children under 13. Bills proposed in Congress would extend online privacy protections to adults. Moreover, proposed legislation in this country and existing laws in foreign countries require companies to establish procedures to notify users of privacy and security policies, obtain consent from users for collection and use of personal information, and/or provide users with the ability to access, correct and delete personal information stored by us. We could become a party to a similar enforcement proceeding. These data protection regulations and enforcement efforts may restrict our ability to collect demographic and personal information from users, which could be costly or harm our marketing efforts.

Risks Relating to the Securities Markets and Ownership of Our Common Stock

        Our stock price may be volatile and you may lose all or a part of your investment.

        Our common stock has been publicly traded only since May 30, 2002. The market price of our common stock has been subject to significant fluctuations since the date of our initial public offering. These fluctuations could continue. It is possible that in some future periods our results of operations may be below the expectations of public market analysts and investors. If this occurs, our stock price may decline. Among the factors that could affect our stock price are as follows:

        In addition, the stock markets have experienced significant price and trading volume fluctuations. These broad market fluctuations may adversely affect the trading price of our common stock. In the past, following periods of volatility in the market price of a public company's securities, securities class action litigation has often been instituted against that company. Such litigation could result in substantial cost and a diversion of management's attention and resources.

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        Our quarterly operating results are volatile and may adversely affect our stock price.

        Our future revenues and operating results are likely to vary significantly from quarter to quarter due to a number of factors, many of which are outside our control, and any of which could harm our business. As a result, we believe that quarterly comparisons of our operating results are not necessarily meaningful and that you should not rely on the results of one quarter as an indication of our future performance. In addition to the other risk factors described in this report, additional factors that have caused and/or could cause our quarterly operating results to fluctuate and in turn affect our stock price include:

        Our operating results may fluctuate depending on the season, and such fluctuations may affect our stock price.

        We have experienced and expect to continue to experience fluctuations in our operating results because of seasonal fluctuations in traditional retail patterns. Sales in the retail and wholesale industry tend to be significantly higher in the fourth calendar quarter of each year than in the preceding three quarters due primarily to increased shopping activity during the holiday season. However, there can be no assurance that our sales in the fourth quarter will exceed those of the preceding quarters or, if the fourth quarter sales do exceed those of the preceding quarters, that we will be able to manage the increased sales effectively. Further, we generally increase our inventories substantially in anticipation of holiday season shopping activity, which has a negative effect on our cash flow. Securities analysts and investors may inaccurately estimate the effects of seasonality on our results of operations in one or more future quarters and, consequently, our operating results may fall below expectations, causing our stock price to decline.

        We do not intend to pay dividends on our non-redeemable common stock, and you may lose the entire amount of your investment.

        We have never declared or paid any cash dividends on our non-redeemable common stock and do not intend to pay dividends on our non-redeemable common stock for the foreseeable future. We intend to invest our future earnings, if any, to fund our growth. Therefore, you will not receive any funds without selling your shares. We cannot assure that you will receive a positive return on your investment when you sell your shares or that you will not lose the entire amount of your investment.

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        Our Amended and Restated Certificate of Incorporation, Amended and Restated Bylaws and the Delaware General Corporation Law contain anti-takeover provisions which could discourage or prevent a takeover, even if an acquisition would be beneficial to our stockholders.

        Several provisions of our Amended and Restated Certificate of Incorporation and Amended and Restated Bylaws could discourage potential acquisition proposals and could delay or prevent a change in control of our company even if that change in control would be beneficial to our stockholders. For example, only one-third of our board of directors will be elected at each of our annual meetings of stockholders, which will make it more difficult for a potential acquirer to change the management of our company, even after acquiring a majority of the shares of our common stock. These provisions, which cannot be amended without the approval of two-thirds of our stockholders, could diminish the opportunities for a stockholder to participate in tender offers, including tender offers at a price above the then current market value of our common stock. In addition, our board of directors, without further stockholder approval, may issue preferred stock, with such terms as the board of directors may determine, that could have the effect of delaying or preventing a change in control of our company. The issuance of preferred stock could also adversely affect the voting powers of the holders of common stock, including the loss of voting control to others. We are also afforded the protections of Section 203 of the Delaware General Corporation Law, which could delay or prevent a change in control of our company or could impede a merger, consolidation, takeover or other business combination involving our company or discourage a potential acquirer from making a tender offer or otherwise attempting to obtain control of our company.

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FORWARD-LOOKING STATEMENTS

        This prospectus includes or incorporates by reference forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. The words "anticipate," "believe," "estimate," "will," "may," "intend" and "expect" and similar expressions generally identify forward-looking statements. Although we believe that our plans, intentions and expectations reflected in the forward-looking statements are reasonable, we cannot be sure that they will be achieved. Important factors that could cause actual results to differ materially from our forward-looking statements are set forth in the section entitled "Risk Factors" in this prospectus, in any section entitled "Risk Factors" in supplements to this prospectus, and in the documents incorporated by reference into this prospectus. These factors are not intended to represent a complete list of the general or specific factors that may affect us. It should be recognized that other factors, including general economic factors and business strategies, may be significant, now or in the future, and the factors set forth in this prospectus may affect us to a greater extent than indicated. All forward-looking statements attributable to us or persons acting on our behalf are expressly qualified in their entirety by the cautionary statements set forth in or incorporated by reference into this prospectus. Except as required by law, we undertake no obligation to update any forward-looking statement, whether as a result of new information, future events or otherwise.


USE OF PROCEEDS

        Unless otherwise indicated in any prospectus supplement, the net proceeds from the sale of securities offered by this prospectus will be used for general corporate purposes and working capital, including sales and marketing activities and inventory purchases. In addition, we may use a portion of the net proceeds to acquire complementary technologies or businesses. However, we currently have no commitments or agreements and are not involved in any negotiations with respect to any such transactions.


RATIO OF EARNINGS TO FIXED CHARGES

        The ratio of earnings to fixed charges for each of the periods indicated is as follows (dollars in thousands):

 
   Year ended December 31,
 
   1999
   2000
   2001
   2002
   2003
   2004
Ratio of earnings to fixed charges     NA     NA     NA     NA     NA     NA
Deficiency of earnings to fixed charges   $ 8,357   $ 21,312   $ 13,806   $ 4,560   $ 11,887   $ 5,002

        For the purpose of this computation, earnings consist of our net loss plus fixed charges. Fixed charges include interest on indebtedness, amortization of borrowing expenses and the portion of rental expense under operating leases deemed by us to be representative of the interest factor. The ratio of earnings to fixed charges was less than 1.00x for all periods presented. Thus, earnings available for fixed charges were inadequate to cover fixed charges for such periods.

        As of the date of this prospectus, we had no preferred stock outstanding.

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DESCRIPTION OF THE DEBT SECURITIES

        Subject to any contractual limitations contained in any credit facility we may enter into, the debt securities may be either secured or unsecured and will either be our senior debt securities or our subordinated debt securities. The debt securities will be issued under one or more separate indentures between us and a trustee. Senior debt securities will be issued under a senior indenture, and subordinated debt securities will be issued under a subordinated indenture. Together, the senior indenture and subordinated indenture are called indentures. This prospectus, together with the applicable prospectus supplement, will describe all the material terms of a particular series of debt securities.

        The following is a summary of selected provisions and definitions of the indentures. The summary of selected provisions of the indentures and the debt securities appearing below is not complete and is subject to, and qualified entirely by reference to, all of the provisions of the applicable indenture and certificates evidencing the applicable debt securities. For additional information, you should read the applicable indenture and the certificate evidencing the applicable debt security.

        The following description sets forth selected general terms and provisions of the applicable indenture and debt securities to which any prospectus supplement may relate. Other specific terms of the applicable indenture and debt securities will be described in the applicable prospectus supplement. If any particular terms of the indenture or debt securities described in a prospectus supplement differ from any of the terms described below, then the terms described below will be deemed to have been superceded by that prospectus supplement.

General

        Debt securities may be issued in separate series without limitation as to aggregate principal amount. We may specify a maximum aggregate principal amount for the debt securities of any series.

        We are not limited as to the amount of debt securities we may issue under the indentures. Unless otherwise provided in a prospectus supplement, a series of debt securities may be reopened to issue additional debt securities of such series.

        The prospectus supplement relating to a particular series of debt securities will set forth:

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        Unless otherwise specified in the prospectus supplement, the debt securities will be registered debt securities.

        Debt securities may be sold at a substantial discount below their stated principal amount, bearing no interest or interest at a rate which at time of issuance is below market rates. The United States Federal income tax considerations applicable to debt securities sold at a discount will be described in the applicable prospectus supplement.

Exchange and Transfer

        Debt securities may be transferred or exchanged at the office of the security registrar or at the office of any transfer agent designated by us.

        We will not impose a service charge for any transfer or exchange, but we may require holders to pay any tax or other governmental charges that may be imposed in connection with any transfer or exchange.

        In the event of any partial redemption of debt securities of any series, we will not be required to:

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        We have initially appointed the trustee as the security registrar. Any transfer agent, and any other security registrar, will be named in the prospectus supplement. We may designate additional transfer agents or change transfer agents or change the office of the transfer agent. However, we will be required to maintain a transfer agent in each place of payment for the debt securities of each series.

Global Securities

        The debt securities of any series may be represented, in whole or in part, by one or more global securities. Each global security will:

        No global security may be exchanged in whole or in part for debt securities registered in the name of any person other than the depositary or any nominee unless:

        As long as the depositary, or its nominee, is the registered owner of a global security, the depositary or nominee will be considered the sole owner and holder of the debt securities represented by the global security for all purposes under the indentures. Except in the above limited circumstances, owners of beneficial interests in a global security will not be:

        Payments on a global security will be made to the depositary or its nominee as the holder of the global security. Some jurisdictions have laws that require that certain purchasers of securities take physical delivery of such securities in definitive form. These laws may impair the ability to transfer beneficial interests in a global security.

        Institutions that have accounts with the depositary or its nominee are referred to as "participants." Ownership of beneficial interests in a global security will be limited to participants and to persons that may hold beneficial interests through participants. The depositary will credit, on its book-entry registration and transfer system, the respective principal amounts of debt securities represented by the global security to the accounts of its participants.

        Ownership of beneficial interests in a global security will be shown on and effected through records maintained by the depositary, with respect to participants' interests, or any participant, with respect to interests of persons held by participants on their behalf.

        Payments, transfers and exchanges relating to beneficial interests in a global security will be subject to policies and procedures of the depositary. The depositary policies and procedures may change from

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time to time. Neither we nor any trustee will have any responsibility or liability for the depositary's or any participant's records with respect to beneficial interests in a global security.

Payment and Paying Agents

        Unless otherwise indicated in a prospectus supplement, the provisions described in this paragraph will apply to the debt securities. Payment of interest on a debt security on any interest payment date will be made to the person in whose name the debt security is registered at the close of business on the regular record date. Payment on debt securities of a particular series will be payable at the office of a paying agent or paying agents designated by us. However, at our option, we may pay interest by mailing a check to the record holder. The corporate trust office will be designated as our sole paying agent.

        We may also name any other paying agents in a prospectus supplement. We may designate additional paying agents, change paying agents or change the office of any paying agent. However, we will be required to maintain a paying agent in each place of payment for the debt securities of a particular series.

        All moneys paid by us to a paying agent for payment on any debt security which remain unclaimed for a period ending the earlier of:

will be repaid to us. Thereafter, the holder may look only to us for such payment.

No Protection in the Event of a Change of Control

        Unless otherwise indicated in a prospectus supplement with respect to a particular series of debt securities, the debt securities will not contain any provisions which may afford holders of the debt securities protection in the event we have a change in control or in the event of a highly leveraged transaction (whether or not such transaction results in a change in control).

Covenants

        Unless otherwise indicated in a prospectus supplement, the debt securities will not contain any financial or restrictive covenants, including covenants restricting either us or any of our subsidiaries from incurring, issuing, assuming or guarantying any indebtedness secured by a lien on any of our or our subsidiaries' property or capital stock, or restricting either us or any of our subsidiaries from entering into sale and leaseback transactions.

Consolidation, Merger and Sale of Assets

        Unless we indicate otherwise in a prospectus supplement, we may not consolidate with or merge into any other person, in a transaction in which we are not the surviving corporation, or convey, transfer or lease our properties and assets substantially as an entirety to any person, unless:

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Events of Default

        Unless we indicate otherwise in a prospectus supplement, the following will be events of default for any series of debt securities under the indentures:

        Additional or different events of default applicable to a series of debt securities may be described in a prospectus supplement. An event of default of one series of debt securities is not necessarily an event of default for any other series of debt securities.

        The trustee may withhold notice to the holders of any default, except defaults in the payment of principal, premium, if any, interest, any sinking fund installment on, or with respect to any conversion right of, the debt securities of such series. However, the trustee must consider it to be in the interest of the holders of the debt securities of such series to withhold this notice.

        Unless we indicate otherwise in a prospectus supplement, if an event of default, other than an event of default described in clause (5) above, shall occur and be continuing, either the trustee or the holders of at least a 25 percent in aggregate principal amount of the outstanding securities of that series may declare the principal amount and premium, if any, of the debt securities of that series, or if any debt securities of that series are original issue discount securities, such other amount as may be specified in the applicable prospectus supplement, in each case together with accrued and unpaid interest, if any, thereon, to be due and payable immediately.

        If an event of default described in clause (5) above shall occur, the principal amount and premium, if any, of all the debt securities of that series, or if any debt securities of that series are original issue discount securities, such other amount as may be specified in the applicable prospectus supplement, in each case together with accrued and unpaid interest, if any, thereon, will automatically become immediately due and payable. Any payment by us on the subordinated debt securities following any such acceleration will be subject to the subordination provisions described below under "Subordinated debt securities."

        After acceleration the holders of a majority in aggregate principal amount of the outstanding securities of that series may, under certain circumstances, rescind and annul such acceleration if all events of default, other than the non-payment of accelerated principal, or other specified amounts, have been cured or waived.

        Other than the duty to act with the required care during an event of default, the trustee will not be obligated to exercise any of its rights or powers at the request of the holders unless the holders shall have offered to the trustee reasonable security or indemnity. Generally, the holders of a majority in aggregate principal amount of the outstanding debt securities of any series will have the right to direct the time, method and place of conducting of any proceeding for any remedy available to the trustee or exercising any trust or power conferred on the trustee.

        A holder will not have any right to institute any proceeding with respect to the indentures, or for the appointment of a receiver or a trustee, or for any other remedy under the indentures, unless:

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        Holders may, however, sue to enforce the payment of principal, premium or interest on any debt security on or after the due date or to enforce the right, if any, to convert any debt security (if the debt security is convertible) without following the procedures listed in (1) through (3) above.

        We will furnish the trustee an annual statement by our officers as to whether or not we are in default in the performance of the terms, provisions and conditions of the indenture and, if so, specifying all known defaults.

Modification and Waiver

        Unless we indicate otherwise in a prospectus supplement, Overstock.com and the applicable trustee may make modifications and amendments to an indenture with the consent of the holders of a majority in aggregate principal amount of the outstanding securities of each series affected by the modification or amendment.

        We may also make modifications and amendments to the indentures for the benefit of holders without their consent, for certain purposes including, but not limited to:

        However, neither we nor the trustee may make any modification or amendment without the consent of the holder of each outstanding security of that series affected by the modification or amendment if such modification or amendment would:

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Satisfaction and Discharge; Defeasance

        We may be discharged from our obligations on the debt securities of any series that have matured or will mature or be redeemed within one year if we deposit enough money with the trustee to pay all the principal, interest and any premium due to the stated maturity date or redemption date of the debt securities.

        Each indenture contains a provision that permits us to elect either or both of the following:


        To make either of the above elections, we must deposit in trust with the trustee enough money to pay in full the principal, interest and premium on the debt securities. This amount may be made in cash and/or United States government obligations or, in the case of debt securities that are denominated in a currency other than United States dollars, cash in the currency in which the debt securities are denominated and/or foreign government obligations. As a condition to either of the above elections, for debt securities denominated in United States dollars we must deliver to the trustee an opinion of counsel that the holders of the debt securities will not recognize income, gain or loss for federal income tax purposes as a result of the action.

        "foreign government obligations" means, with respect to debt securities of any series that are denominated in a currency other than United States dollars:

Notices

        Notices to holders will be given by mail to the addresses of the holders in the security register.

Governing Law

        The indentures and the debt securities will be governed by, and construed under, the laws of the State of New York.

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No Personal Liability of Directors, Officers, Employees and Stockholders

        No incorporator, stockholder, employee, agent, officer, director or subsidiary of ours will have any liability for any obligations of ours, or because of the creation of any indebtedness under the debt securities, the indentures or supplemental indentures. The indentures provide that all such liability is expressly waived and released as a condition of, and as a consideration for, the execution of such indentures and the issuance of the debt securities.

Regarding the Trustee

        The indentures limit the right of the trustee, should it become a creditor of Overstock.com, to obtain payment of claims or secure its claims.

        The trustee is permitted to engage in certain other transactions. However, if the trustee acquires any conflicting interest, and there is a default under the debt securities of any series for which they are trustee, the trustee must eliminate the conflict or resign.

Subordinated Debt Securities

        The indebtedness evidenced by the subordinated debt securities of any series is subordinated, to the extent provided in the subordinated indenture and the applicable prospectus supplement, to the prior payment in full, in cash or other payment satisfactory to the holders of senior debt, of all senior debt, including any senior debt securities.

        Upon any distribution of our assets upon any dissolution, winding up, liquidation or reorganization, payments on the subordinated debt securities will be subordinated in right of payment to the prior payment in full, in cash or other payment satisfactory to holders of senior debt, of all senior debt.

        In the event of any acceleration of the subordinated debt securities because of an event of default, holders of any senior debt would be entitled to payment in full, in cash or other payment satisfactory to holders of senior debt, of all senior debt before the holders of subordinated debt securities are entitled to receive any payment or distribution.

        We are required to promptly notify holders of senior debt under the subordinated indenture if payment of the subordinated debt securities is accelerated because of an event of default.

        Under the subordinated indenture, we may also not make payment on the subordinated debt securities if:

        We may and shall resume payments on the subordinated debt securities:

        No new payment blockage period may start unless 365 days have elapsed from the effectiveness of the prior payment blockage notice.

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        No nonpayment default that existed or was continuing on the date of delivery of any payment blockage notice to the trustee shall be the basis for a subsequent payment blockage notice.

        As a result of these subordination provisions, in the event of our bankruptcy, dissolution or reorganization, holders of senior debt may receive more, ratably, and holders of the subordinated debt securities may receive less, ratably, than our other creditors. The subordination provisions will not prevent the occurrence of any event of default under the subordinated indenture.

        The subordination provisions will not apply to payments from money or government obligations held in trust by the trustee for the payment of principal, interest and premium, if any, on subordinated debt securities pursuant to the provisions described under "—Satisfaction and discharge; defeasance," if the subordination provisions were not violated at the time the money or government obligations were deposited into trust.

        If the trustee or any holder receives any payment that should not have been made to them in contravention of subordination provisions before all senior debt is paid in full in cash or other payment satisfactory to holders of senior debt, then such payment will be held in trust for the holders of senior debt.

        Senior debt securities will constitute senior debt under the subordinated indenture.

        Additional or different subordination provisions may be described in a prospectus supplement relating to a particular series of debt securities.

        "designated senior debt" means our obligations under any of our senior debt that expressly provides that it is "designated senior debt."

        "indebtedness" means:

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        "senior debt" means the principal of, premium, if any, interest, including all interest accruing subsequent to the commencement of any bankruptcy or similar proceeding, rent and all fees, costs, expenses and other amounts accrued or due on or in connection with our indebtedness, including all deferrals, renewals, extensions or refundings of, or modifications or supplements to, that indebtedness. Senior debt shall not include:

        "subsidiary" means any entity of which at least a majority of the outstanding voting stock having the power to elect a majority of the board of directors of such entity (in the case of a corporation) is, or of which at least a majority of the equity interests (in the case of an entity which is not a corporation) are at the time owned, directly or indirectly, by us or by one or more or our other subsidiaries or by a combination of us and our other subsidiaries. For purposes of this definition, "voting stock" means stock which ordinarily has voting power for the election of directors, whether at all times or only so long as no senior class of stock has such voting power by reason of any contingency.

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DESCRIPTION OF COMMON STOCK

        The following description of our common stock does not purport to be complete and is subject to and qualified in its entirety by reference to the more complete descriptions set forth in our certificate of incorporation, as amended, and our bylaws, as amended. We have filed these documents as exhibits to the registration statement related to this prospectus.

General

        We are authorized to issue 100,000,000 shares of common stock, $0.0001 par value, and 5,000,000 shares of preferred stock, $0.0001 par value, in one or more series. As of December 31, 2004, there were 19,819,232 shares of common stock issued and outstanding.

        Each holder of common stock is entitled to one vote for each share held on all matters to be voted upon by the stockholders, and there are no cumulative voting rights. Subject to preferences that may be applicable to any outstanding preferred stock, holders of common stock are entitled to receive ratably the dividends, if any, that are declared from time to time by the board of directors out of funds legally available for that purpose. If there is a liquidation, dissolution or winding up of the company, the holders of common stock are entitled to share in any assets remaining after the payment of liabilities and the satisfaction of any liquidation preference granted to the holders of any outstanding shares of preferred stock. Holders of common stock have no preemptive or conversion rights or other subscription rights. There are no redemption or sinking fund provisions applicable to the common stock. All outstanding shares of common stock are fully paid and nonassessable. The powers, preferences and rights of the holders of common stock are subject to, and may be adversely affected by, the rights of the holders of shares of any series of preferred stock that we may designate in the future.

Other Obligations to Issue Capital Stock

        We have adopted and maintain equity incentive plans pursuant to which we are authorized to issue stock, stock options and other types of compensation for employees, directors, consultants and other persons who provide services to us. Additionally, we have issued warrants to certain stockholders in connection with the purchase of common stock. As of December 31, 2004, we had outstanding options and warrants to acquire 2,398,636 shares of common stock. As of December 31, 2004, we have reserved an additional 1,184,158 shares of common stock for future issuance under these incentive plans.

        In November 2004, we completed an offering of $120.0 million of 3.75% Convertible Senior Notes (the "Senior Notes"). The Senior Notes are convertible at any time prior to maturity into our common stock at the option of the note holders at a conversion price of $76.23 per share or a total of approximately 1,574,184 shares (subject to adjustment in certain events, including stock splits, dividends and other distributions and certain repurchases of our stock, as well as certain fundamental changes in the ownership of the Company).

Anti-Takeover Provisions

        We are subject to the provisions of Section 203 of the Delaware General Corporation Law, an anti-takeover law. In general, the statute prohibits a publicly held Delaware corporation from engaging in a "business combination" with an "interested stockholder" for a period of three years after the date of the transaction in which the person became an interested stockholder, unless the business combination is approved in a prescribed manner. For purposes of Section 203, a "business combination" includes a merger, asset sale or other transaction resulting in a financial benefit to the interested stockholder, and an "interested stockholder" is a person who, together with affiliates and

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associates, owns (or within three years prior, did own) 15 percent or more of the corporation's voting stock. A corporation may "opt out" of this statute, which we have not done.

        Our certificate of incorporation, as amended, and bylaws, as amended, include the following provisions, among others, that could discourage potential acquisition proposals and could delay or prevent a change of control of Overstock.com:

        In addition, the authorization of undesignated preferred stock makes it possible for the board of directors to issue preferred stock with voting or other rights or preferences that could impede the success of any attempt to change control of Overstock.com.

Transfer Agent and Registrar

        The transfer agent and registrar for our common stock is EquiServe Trust Company, N.A. EquiServe's address is 150 Royal Street, Canton, MA 02021, and its telephone number is 1-800-733-5001.

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DESCRIPTION OF PREFERRED STOCK

        We are authorized to issue 5,000,000 shares of preferred stock, $0.0001 par value. No shares of preferred stock are outstanding as of the date of this prospectus.

        Our board of directors has the authority, without stockholder consent, subject to certain limitations imposed by law or our bylaws, to issue one or more series of preferred stock at any time. The rights, preferences and restrictions of the preferred stock of each series will be fixed by the certificate of designation relating to each particular series. A prospectus supplement relating to each such series will specify the terms of the preferred stock as determined by our board of directors, including the following:

        We will describe the specific terms of a particular series of preferred stock in the prospectus supplement relating to that series. The description of preferred stock set forth above and in any description of the terms of a particular series of preferred stock in the related prospectus supplement will not be complete. You should refer to the applicable certificate of designation for such series of preferred stock for complete information with respect to such preferred stock. The prospectus supplement will also contain a description of certain United States federal income tax consequences relating to the preferred stock.


DESCRIPTION OF THE WARRANTS

General

        We may issue warrants for the purchase of debt securities, preferred stock, common stock or units, or any combination thereof. Warrants may be issued independently or together with debt securities, preferred stock common stock or units and may be attached to or separate from any offered securities. Each series of warrants will be issued under a separate warrant agreement to be entered into between us and a bank or trust company, as warrant agent. The warrant agent will act solely as our agent in connection with the warrants. The warrant agent will not have any obligation or relationship of agency or trust for or with any holders or beneficial owners of warrants. This summary of certain provisions of the warrants is not complete. For the complete terms of a particular series of warrants, you should refer to the prospectus supplement for that series of warrants and the warrant agreement for that particular series.

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Debt Warrants

        The prospectus supplement relating to a particular issue of warrants to purchase debt securities will describe the terms of the debt warrants, including the following:

        Debt warrant certificates will be exchangeable for new debt warrant certificates of different denominations. Debt warrants may be exercised at the corporate trust office of the warrant agent or any other office indicated in the prospectus supplement. Prior to the exercise of their debt warrants, holders of debt warrants will not have any of the rights of holders of the debt securities purchasable upon exercise and will not be entitled to payment of principal or any premium, if any, or interest on the debt securities purchasable upon exercise.

Stock Warrants

        The prospectus supplement relating to a particular series of warrants to purchase our common stock or preferred stock will describe the terms of the warrants, including the following:

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        Holders of equity warrants will not be entitled:

        As set forth in the applicable prospectus supplement, the exercise price and the number of shares of common stock or preferred stock purchasable upon exercise of the warrant will be subject to adjustment in certain events, including the issuance of a stock dividend to any holders of common stock, a stock split, reverse stock split, combination, subdivision or reclassification of common stock, and such other events, if any, specified in the applicable prospectus supplement.

Unit Warrants

        The prospectus supplement relating to a particular issue of warrants to purchase units (see "Description of Units") will describe the terms of the unit warrants, including the number and type of units that can be purchased upon exercise and the price of those units.

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DESCRIPTION OF STOCK PURCHASE CONTRACTS

        We may issue stock purchase contracts. This section outlines some of the provisions of the stock purchase contracts we may issue, and of the related purchase contract agreement and the pledge agreement. This information is not complete in all respects and is qualified entirely by reference to the purchase contract agreement and pledge agreement with respect to the stock purchase contracts of any particular series. The specific terms of any series of stock purchase contracts will be described in a prospectus supplement. If so described in a particular supplement, the specific terms of any series of stock purchase contracts may differ from the general description of terms presented below.

        Unless otherwise specified in the prospectus supplement, we may issue stock purchase contracts, including contracts obligating holders to purchase from us and us to sell to the holders, a specified number of shares of common stock or preferred stock at a future date or dates. Alternatively, the stock purchase contracts may obligate us to purchase from holders, and obligate holders to sell to us, a specified or varying number of shares of common stock or preferred stock. The consideration per share of common stock or preferred stock may be fixed at the time the stock purchase contracts are issued or may be determined by a specific reference to a formula set forth in the stock purchase contracts. The stock purchase contracts may provide for settlement by delivery by or on behalf of Overstock.com of shares of common stock or preferred stock or it may provide for settlement by reference or linkage to the value, performance or trading price of our common stock or preferred stock. The stock purchase contracts may be issued separately or as part of stock purchase units consisting of a stock purchase contract and debt securities, preferred stock or debt obligations of third parties, including U.S. treasury securities, other stock purchase contracts or common stock, securing the holders' obligations to purchase or sell, as the case may be, the common stock or the preferred stock under the stock purchase contracts. The stock purchase contracts may require us to make periodic payments to the holders of the stock purchase units or vice versa, and such payments may be unsecured or prefunded on some basis and may be paid on a current or on a deferred basis. The stock purchase contracts may require holders to secure their obligations thereunder in a specified manner and may provide for the prepayment of all or part of the consideration payable by holders in connection with the purchase of common stock or preferred stock pursuant to the stock purchase contracts.

        The securities related to the stock purchase contracts may be pledged to a collateral agent for Overstock.com's benefit pursuant to a pledge agreement to secure the obligations of holders of stock purchase contracts to purchase common stock or preferred stock under the related stock purchase contracts. The rights of holders of stock purchase contracts to the related pledged securities will be subject to Overstock.com's security interest therein created by the pledge agreement. No holder of stock purchase contracts will be permitted to withdraw the pledged securities related to such stock purchase contracts from the pledge arrangement except upon the termination or early settlement of the related stock purchase contracts or in the event other securities, cash or property is made subject to the pledge agreement in lieu of the pledged securities, if permitted by the pledge agreement, or as otherwise provided in the pledge agreement. Subject to such security interest and the terms of the purchase contract agreement and the pledge agreement, each holder of a stock purchase contract will retain full beneficial ownership of the related pledged securities.

        Except as described in the prospectus supplement, the collateral agent will, upon receipt of distributions on the pledged securities, distribute such payments to Overstock.com or the purchase contract agent, as provided in the pledge agreement. The purchase agent will in turn distribute payments it receives as provided in the purchase contract agreement.

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DESCRIPTION OF UNITS

        We may issue units. This section outlines some of the provisions of the units we may issue and of the related unit agreements. This information may not be complete in all respects and is qualified entirely by reference to the unit agreement with respect to the units of any particular series. The specific terms of any series of units will be described in a prospectus supplement. If so described in a particular supplement, the specific terms of any series of units may differ from the general description of terms presented below.

        We may issue units comprised of one or more debt securities, shares of common stock, shares of preferred stock, stock purchase contracts and warrants in any combination. Each unit will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each included security. The unit agreement under which a unit is issued may provide that the securities included in the unit may not be held or transferred separately, at any time or at any time before a specified date.

        The prospectus supplement may describe:

        The provisions described in this section, as well as the applicable descriptions included under "Description of the Debt Securities", "Description of Preferred Stock", "Description of Common Stock", "Description of the Warrants" and "Description of Stock Purchase Contracts", will apply to each unit and to any debt security, preferred stock, common stock, warrant or stock purchase contract included in each unit, respectively.

Issuance in Series

        We may issue units in such amounts and in as many distinct series as we wish. This section summarizes terms of the units that apply generally to all series. Most of the financial and other specific terms of each series will be described in the prospectus supplement.

Unit Agreements

        We will issue the units under one or more unit agreements to be entered into between us and a bank or other financial institution, as unit agent. We may add, replace or terminate unit agents from time to time. We will identify the unit agreement under which each series of units will be issued and the unit agent under that agreement in the prospectus supplement.

        The following provision will generally apply to all unit agreements unless otherwise stated in the prospectus supplement.

Enforcement of Rights

        The unit agent under a unit agreement will act solely as our agent in connection with the units issued under that agreement. The unit agent will not assume any obligation or relationship of agency or trust for or with any holders of those units or of the securities comprising those units. The unit agent will not be obligated to take any action on behalf of those holders to enforce or protect their rights under the units or the included securities.

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        Except as indicated in the next paragraph, a holder of a unit may, without the consent of the unit agent or any other holder, enforce its rights as holder under any security included in the unit, in accordance with the terms of that security and the indenture, warrant agreement or other instrument under which that security is issued. Those terms are described elsewhere in this prospectus under the sections relating to debt securities, preferred stock, common stock and warrants.

        Notwithstanding the foregoing, a unit agreement may limit or otherwise affect the ability of a holder of units issued under that agreement to enforce its rights, including any right to bring a legal action, with respect to those units or any securities, other than debt securities, that are included in those units. Limitations of this kind will be described in the prospectus supplement.

Modification Without Consent of Holders

        We and the applicable unit agent may amend any unit or unit agreement without the consent of any holder:

        We do not need any approval to make changes that affect only units to be issued after the changes take effect. We may also make changes that do not adversely affect a particular unit in any material respect, even if they adversely affect other units in a material respect. In those cases, we do not need to obtain the approval of the holder of the unaffected unit; we need only obtain any required approvals from the holders of the affected units.

Modification With Consent of Holders

        We may not amend any particular unit or a unit agreement with respect to any particular unit unless we obtain the consent of the holder of that unit, if the amendment would:

        Any other change to a particular unit agreement and the units issued under that agreement would require the following approval:

        These provisions regarding changes with majority approval also apply to changes affecting any securities issued under a unit agreement, as the governing document.

        In each case, the required approval must be given by written consent.

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Unit Agreements Will Not Be Qualified Under Trust Indenture Act

        No unit agreement will be qualified as an indenture, and no unit agent will be required to qualify as a trustee, under the Trust Indenture Act. Therefore, holders of units issued under unit agreements will not have the protections of the Trust Indenture Act with respect to their units.

Title

        Overstock.com, the unit agents and any of their agents may treat the registered holder of any unit certificate as an absolute owner of the units evidenced by that certificate for any purpose and as the person entitled to exercise the rights attaching to the units so requested, despite any notice to the contrary. See "Legal Ownership of Securities".


LEGAL OWNERSHIP OF SECURITIES

        We may issue securities in book-entry form only, as we will specify in the applicable prospectus supplement. This means that securities may be represented by one or more global securities registered in the name of a financial institution that holds them as depositary on behalf of other financial institutions that participate in the depositary's book-entry system. Only the person in whose name a security is registered is recognized as the holder of that security. Consequently, for securities issued in global form, we will recognize only the depositary as the holder of the securities, and we will make all payments on the securities to the depositary. The depositary passes along the payments it receives to its participants, which in turn pass the payments along to their customers who are the beneficial owners. As a result, investors in a book-entry security will not own securities directly. Instead, they will own beneficial interests in a global security, through a bank, broker or other financial institution that participates in the depositary's book-entry system or holds an interest through a participant. As long as the securities are issued in global form, investors will be indirect holders, and not holders, of the securities. If the prospectus supplement for a particular security indicates that the security will be issued in global form only, then the security will be represented by a global security at all times unless and until the global security is terminated. If termination occurs, we may issue the securities through another book-entry clearing system or decide that the securities may no longer be held through any book-entry clearing system.

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PLAN OF DISTRIBUTION

        We may sell the securities offered under this prospectus from time to time in one or more transactions:

        We will bear all costs, fees and expenses incurred in connection with the registration of the offering of securities under this prospectus.

        We may sell the securities at a fixed price or prices, which may be changed, at market prices prevailing at the time of sale, at prices relating to the prevailing market prices or at negotiated prices. The distribution of the securities may be effected from time to time in one or more transactions, by means of one or more of the following transactions, which may include:

        We may determine the price or other terms of the securities offered in this prospectus or any applicable prospectus supplement by use of an electronic auction. We will describe how any auction will determine the price or any other terms, how potential investors may participate in the auction and the nature of the obligations of the underwriter, dealer or agent in the applicable prospectus supplement.

        Each time we offer securities pursuant to this prospectus, the prospectus supplement, if required, will set forth:

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        Any initial public offering prices, discounts or concessions allowed or reallowed or paid to dealers may be changed from time to time.

        Underwriters, dealers or agents may receive compensation in the form of discounts, concessions or commissions from us or from our purchasers (as their agents in connection with the sale of securities). The compensation received may be in excess of customary discounts, concessions or commissions. Any underwriters, dealers, agents or other purchasers participating in the distribution of the securities may be considered "underwriters" under the Securities Act of 1933, as amended. As a result, discounts, commissions, or profits on resale received by them on the sale of the securities may be treated as underwriting discounts and commissions.

        Underwriters, dealers and agents may be entitled, under agreements entered into with us, to indemnification by us against certain civil liabilities, including liabilities under the Securities Act of 1933, as amended, or to contribution with respect to payments made by the underwriters, dealers or agents, under agreements between us and the underwriters, dealers and agents. The terms and conditions of this indemnification or contribution will be described in the applicable prospectus supplement. Underwriters or agents and their associates may be customers of, engage in transactions with, or perform services for, us in the ordinary course of business.

        We may authorize our respective agents or underwriters to solicit offers to purchase securities at the public offering price under delayed delivery contracts. The terms of these delayed delivery contracts, including when payment for and delivery of the securities sold will be made under the contracts and any conditions to each party's performance set forth in the contracts, will be described in the applicable prospectus supplement. The compensation received by underwriters or agents soliciting purchase of securities under delayed delivery contracts will also be described in the applicable prospectus supplement.

        We may grant underwriters who participate in the distribution of securities an option to purchase additional securities to cover over-allotments, if any, in connection with the distribution, at the public offering price, with additional underwriting commissions or discounts, as may be set forth in a related prospectus supplement. The terms of any over-allotment option will be set forth in the prospectus supplement for those securities.

        If underwriters or dealers are used in the sale, the securities will be acquired by the underwriters or dealers for their own account and may be resold from time to time in one or more transactions, at a fixed price or prices, which may be changed, or at market prices prevailing at the time of sale, or at prices relating to such prevailing market prices, or at negotiated prices. The securities may be offered to the public, at varying prices to be determined at the time of resale, either through underwriting syndicates represented by one or more managing underwriters or directly by one or more of such firms. The names of the specific managing underwriter or underwriters, as well as any other underwriters, and the terms of the transactions, including compensation of the underwriters and dealers, which may be in the form of discounts, concessions or commissions, if any, will be described in the applicable prospectus supplement, which will be used by the underwriters to make resales of the securities. Unless otherwise set forth in the prospectus supplement, the obligations of the underwriters or dealers to purchase the securities offered will be subject to certain conditions precedent and the underwriters or dealers will be obligated to purchase all the offered securities if any are purchased.

        The securities may be sold directly by us or through agents designated by us from time to time. We may solicit offers to purchase the securities directly, and we may sell the securities directly to institutional or other investors, who may be deemed an underwriter within the meaning of the Securities Act of 1933 with respect to any resales of those securities. The terms of these sales, including the terms of any bidding or auction process, if utilized, will be described in the applicable prospectus supplement. Any agent involved in the offer or sale of the securities in respect of which this prospectus

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is delivered will be named in the prospectus supplement. Unless otherwise indicated, any such agent will be acting on a best efforts only basis for the period of its appointment.

        To the extent that we make sales to or through one or more underwriters or agents in at-the-market offerings, we will do so pursuant to the terms of a distribution agreement between us and the underwriters or agents. If we engage in at-the-market sales pursuant to a distribution agreement, we will issue and sell shares of our common stock to or through one or more underwriters or agents, which may act on an agency basis or on a principal basis. During the term of any such agreement, we may sell shares on a daily basis in exchange transactions or otherwise as we agree with the underwriters or agents. The distribution agreement will provide that any shares of our common stock sold will be sold at prices related to the then prevailing market prices for our common stock. Therefore, exact figures regarding proceeds that will be raised or commissions that will be paid cannot be determined at this time and we will describe them in a prospectus supplement. Pursuant to the terms of the distribution agreement, we also may agree to sell, and the relevant underwriters or agents may agree to solicit offers to purchase, blocks of our common stock or other securities. The terms of each such distribution agreement will be set forth in more detail in a prospectus supplement to this prospectus. In the event that any underwriter or agent acts as principal, or broker-dealer acts as underwriter, it may engage in certain transactions that stabilize, maintain or otherwise affect the price of our securities.

        In connection with the offering of the securities, certain underwriters and selling group members and their respective affiliates, may engage in transactions that stabilize, maintain or otherwise affect the market price of the applicable securities. These transactions may include stabilization transactions effected in accordance with Rule 104 of Regulation M promulgated by the SEC pursuant to which these persons may bid for or purchase securities for the purpose of stabilizing their market price. Neither we nor any underwriter make any representation or prediction as to the direction or magnitude of any effect that the transactions described above may have on the price of the securities. In addition, neither we nor any underwriter make any representation that such underwriter will engage in such transactions or that such transactions, once commenced, will not be discontinued without notice.

        We and the underwriters may engage in derivative transactions involving the securities. These derivatives may consist of short sale transactions and other hedging activities. The underwriters may acquire a long or short position in the securities, hold or resell securities acquired and purchase options or futures on the securities and other derivative instruments with returns linked to or related to changes in the price of the securities. In order to facilitate these derivative transactions, we may enter into security lending or repurchase agreements with the underwriters. The underwriters may effect the derivative transactions through sales of the securities to the public, including short sales, or by lending the securities in order to facilitate short sale transactions by others. The underwriters may also use the securities purchased or borrowed from us or others (or, in the case of derivatives, securities received from us in settlement of those derivatives) or by exercising any over-allotment option granted to them by us to directly or indirectly settle sales of the securities or close out any related open borrowings of the securities.

        In addition, any managing underwriter may impose "penalty bids" under contractual arrangements with other underwriters, which means that they can reclaim from an underwriter (or any selling group member participating in the offering) for the account of the other underwriters, the selling concession for the securities that are distributed in the offering but subsequently purchased for the account of the underwriters in the open market. Any of the transactions described in this paragraph or comparable transactions that are described in any accompanying prospectus supplement may result in the maintenance of the price of the securities at a level above that which might otherwise prevail in the open market. None of the transactions described above or in an accompanying prospectus supplement are required to be taken by any underwriters and, if they are undertaken, may be discontinued at any time.

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        If indicated in the applicable prospectus supplement, we will authorize underwriters, dealers or agents to solicit offers by institutional investors to purchase securities from us pursuant to contracts providing for payment and delivery at a future date. In all cases, these purchasers must be approved by us. Unless otherwise set forth in the applicable prospectus supplement, the obligations of any purchaser under any of these contracts will not be subject to any conditions, except that the purchase of the securities must not at the time of delivery be prohibited under the laws of any jurisdiction to which that purchaser is subject and if securities also are being sold to underwriters, we must have sold to these underwriters the securities not subject to delayed delivery. Underwriters and other agents will not have any responsibility in respect of the validity or performance of these contracts.

        Our common stock is listed on the Nasdaq National Market under the symbol "OSTK." Any shares of common stock sold pursuant to a prospectus supplement will be listed on the Nasdaq National Market. Any underwriters or agents to or through which we may sell securities may make a market in the securities, but these underwriters or agents will not be obligated to do so and any of them may discontinue any market making at any time without notice. We cannot, therefore, give any assurance as to the liquidity of our trading market for any securities that we may sell.

        Under the securities laws of some states, the securities registered by the registration statement that includes this prospectus may be sold in those states only through registered or licensed brokers or dealers. In addition, in some states, securities may not be sold unless they have been registered or qualified for sale in the applicable state or an exemption from the resignation or qualification requirement is available and complied with.

        Any person participating in the distribution of the securities registered under the registration statement that includes this prospectus will be subject to applicable provisions of the Securities Exchange Act of 1934, and the applicable rules and regulations of the SEC, including, among others, Regulation M noted above, which may limit the timing of purchases and sales of any of the securities by any such person. Furthermore, Regulation M may restrict the ability of any person engaged in the distribution of the securities to engage in market-making activities with respect to the securities. These restrictions may affect the marketability of the securities and the ability of any person or entity to engage in market-making activities with respect to the securities.


VALIDITY OF THE SECURITIES

        The validity of the securities offered hereby will be passed upon for us by Bracewell & Giuliani LLP, Austin, Texas. Any underwriters will be represented by their own legal counsel.


EXPERTS

        The consolidated financial statements of Overstock.com, Inc. incorporated in this Prospectus by reference to Overstock.com, Inc.'s Annual Report on Form 10-K for the year ended December 31, 2004 have been so incorporated in reliance on the report of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.


WHERE YOU CAN FIND MORE INFORMATION

        We file annual, quarterly and current reports, proxy statements and other information with the SEC. You may read and copy any document we file with the SEC at the SEC's public reference room at 450 Fifth Street, N.W., Washington, D.C., 20549. Please call the SEC at 1-800-SEC-0330 for further information on the operation of the Public Reference Room. The SEC maintains an Internet site that contains reports, proxy and information statements and other information regarding issuers that file electronically with the SEC. The address of that site is http://www.sec.gov. Additionally, we make these filings available, free of charge, on www.overstock.com as soon as reasonably practicable after we

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electronically file such materials with, or furnish them to, the SEC. The information on the website listed above, other than these filings, is not, and should not be, considered part of this prospectus and is not incorporated by reference into this document.

        We have filed with the SEC a registration statement on Form S-3 under the Securities Act of 1933, as amended, with respect to the securities offered in connection with this prospectus. This prospectus does not contain all of the information set forth in the registration statement. We have omitted certain parts of the registration statement in accordance with the rules and regulations of the SEC. For further information with respect to us and the securities we may offer, you should refer to the registration statement. Statements contained in this prospectus as to the contents of any contract or other document are not necessarily complete and, in each instance, you should refer to the copy of such contract or document filed as an exhibit to or incorporated by reference in the registration statement. Each statement as to the contents of such contract or document is qualified in all respects by such reference. You may obtain copies of the registration statement from the SEC's principal office in Washington, D.C. upon payment of the fees prescribed by the SEC, or you may examine the registration statement without charge at the SEC's public reference room described above.

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DOCUMENTS INCORPORATED BY REFERENCE

        The SEC allows us to "incorporate by reference" the information we file with them, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this prospectus, and information that we file later with the SEC will automatically update and supersede this information. We incorporate by reference the documents listed below and any future filings we will make with the SEC prior to the termination of the offering under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934:

        The reports and other documents that we file after the date of this prospectus and prior to the termination of this offering shall be deemed to be incorporated by reference into this prospectus and will update, supplement and supersede the information in this prospectus. We will provide to each person, including any beneficial owner to whom a prospectus is delivered, a copy of any or all of the information that has been incorporated by reference in the prospectus but not delivered with the prospectus. We will provide this information upon written or oral request at no cost to the requester. You may request a copy of any of this information by writing us at the following address: Overstock.com, Inc. 6322 South 3000 East, Suite 100, Salt Lake City, Utah 84121, Attention: Investor Relations; or by calling our Investor Relations Department at telephone number (801) 947-3100.

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