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): December 18, 2013

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 December 18, 2013, Duke Energy Corporation (the “Corporation”) and its wholly-owned subsidiaries, Duke Energy Carolinas, LLC, Duke Energy Florida, Inc., Duke Energy Indiana, Inc., Duke Energy Kentucky, Inc., Duke Energy Ohio, Inc., and Duke Energy Progress, Inc., entered into an amendment to the $6,000,000,000 Credit Agreement, dated as of November 18, 2011, among the Corporation and each of such subsidiaries, as Borrowers, the lenders listed therein, Wells Fargo Bank, National Association, as Administrative Agent, Bank of America, N.A. and The Royal Bank of Scotland plc, as Co-Syndication Agents, and Bank of China, New York Branch, Barclays Bank PLC, Citibank, N.A., Credit Suisse AG, Cayman Islands Branch,  JPMorgan Chase Bank, N.A., The Bank of Tokyo-Mitsubishi UFJ, Ltd. and UBS Securities LLC, as Co-Documentation Agents.  The credit facility was originally described and filed in the Corporation’s Form 8-K dated November 25, 2011.  The amendment was entered into primarily to increase the maximum borrowing sublimit available to the Corporation from $2,250,000,000 to $3,000,000,000, and to extend the termination date of the facility by approximately one year, to December 18, 2018. The total amount of $6,000,000,000 available under the Credit Agreement did not change.

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 9.01.   Financial Statements and Exhibits

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SIGNATURE

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

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EXHIBIT INDEX

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