UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): March 16, 2017

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

o Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240. 13e-4(c))

Item 1.01.  Entry into a Material Definitive Agreement.

On March 16, 2017, Duke Energy Corporation (the “Corporation”) and its wholly-owned subsidiaries, Duke Energy Carolinas, LLC, Duke Energy Florida, LLC, Duke Energy Indiana, LLC, Duke Energy Kentucky, Inc., Duke Energy Ohio, Inc., Duke Energy Progress, LLC, and Piedmont Natural Gas Company, Inc. (“Piedmont”), entered into an amendment to the $6,000,000,000 Credit Agreement, dated as of November 18, 2011 and as amended on December 18, 2013, and January 30, 2015, among the Corporation and each of such subsidiaries (except Piedmont, which became a subsidiary in 2016), as Borrowers, the lenders listed therein, and Wells Fargo Bank, National Association, as Administrative Agent and Swingline Lender.  The credit facility was originally described and filed in the Corporation’s Form 8-K dated November 25, 2011.  This amendment was entered into primarily to add Piedmont as a Borrower, to increase the maximum aggregate borrowing amount available to the Borrowers from $7,500,000,000 to $8,000,000,000, and to extend the termination date of the facility from January 30, 2020 to March 16, 2022.

The disclosure in this Item 1.01 is qualified in its entirety by the provisions of the amendment to the Credit Agreement, which is attached hereto as Exhibit 10.1 and is incorporated herein by reference.

Item 8.01.  Other Events.

Coincident with the credit agreement amendment described in Item 1.01 above, the Corporation increased the size of its commercial paper program from $4.0 billion to $4.85 billion.  For more information on the commercial paper program, please refer to the Corporation’s Form 10-K Annual Report for the year ended December 31, 2016.

Also coincident with the credit facility amendment, Piedmont terminated, in accordance with its terms, the Amended and Restated Credit Agreement dated as of October 1, 2012 among Piedmont, Wells Fargo Bank, National Association, as Administrative Agent, Swing Line Lender, L/C Issuer and a Lender, and Branch Banking and Trust Company, Bank of America, N.A., JPMorgan Chase Bank, N.A., PNC Bank, National Association, U.S. Bank National Association and Royal Bank of Canada, each a Lender.

Item 9.01.   Financial Statements and Exhibits

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SIGNATURE

Pursuant to the requirements of the Securities and Exchange Act of 1934, the registrants have duly caused this report to be signed on their behalf by the undersigned hereunto duly authorized.

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EXHIBIT INDEX

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