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): August 6, 2014

DEVON ENERGY CORPORATION

(Exact Name of Registrant as Specified in its Charter)

Registrant’s telephone number, including area code: (405) 235-3611

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:

Item 7.01. Regulation FD Disclosure

In accordance with General Instruction B.2. of Form 8-K, the information presented herein under Item 7.01 shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), nor shall it be deemed incorporated by reference in any filing under the Exchange Act or Securities Act of 1933, as amended, except as expressly set forth by specific reference in such a filing.

Our original 2014 forward-looking estimates are included in our Form 8-K dated February 19, 2014. These estimates were based on our examination of historical operating trends, the information used to prepare our December 31, 2013, reserve reports and other data in our possession or available from third parties.

In February 2014, we announced plans to divest certain non-core properties located throughout Canada and the U.S. On April 1, 2014, we completed the sale of our Canadian conventional assets to Canadian Natural Resources Limited. Additionally, on June 30, 2014, we reached an agreement to sell our U.S. non-core assets to Linn Energy and expect the transaction to close in the third quarter of 2014. Accordingly, we are updating certain of our 2014 forward-looking estimates in this document for the impact of the transactions noted above for the remainder of the year as well as other operational updates. The updated estimates along with estimates that have not changed, are presented in the following pages.

In this report, financial amounts related to our Canadian operations have been converted to U.S. dollars using estimated average exchange rates of $1.00 U.S. dollar to $1.11 Canadian dollar.

Production and Prices

Set forth below are our daily production and price realization estimates for the third quarter and full year 2014. The term “core” refers to our core and emerging assets in the Anadarko Basin, Barnett Shale, Eagle Ford Shale, Mississippian-Woodford Trend, Permian Basin and Rockies Oil in the United States, as well as our Heavy Oil assets in Canada. The term “non-core” refers to our remaining properties, many of which we are in the process of divesting. The price realizations for oil and bitumen are determined using the monthly average of NYMEX settled prices on each trading day for the benchmark West Texas Intermediate crude oil price at Cushing, Oklahoma. The price realizations for natural gas are determined using the first-of-month South Louisiana Henry Hub price index as published in Inside FERC.

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Commodity Price Risk Management

As of July 30, 2014, we had the following oil derivative positions. The first table presents our oil derivatives that settle against the average of the prompt month NYMEX West Texas Intermediate futures price. The second table presents our oil derivatives that settle against the Western Canadian Select index.

As of July 30, 2014, we had the following open natural gas derivative positions. The first table presents our natural gas derivatives that settle against the Inside FERC first-of-the-month Henry Hub index. The second table presents our natural gas derivatives that settle against the AECO index.

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Other Operating and Nonoperating Items

The following table includes third quarter and full year 2014 estimates of other operating and nonoperating items.

Capital Expenditures

Set forth below are our capital expenditure estimates for the third quarter and full year 2014.

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Information Regarding Forward-Looking Estimates

This report includes our 2014 forward-looking estimates and associated forward-looking statements regarding our expectations and plans, as well as future events or conditions. Such forward-looking statements are based on our examination of historical operating trends, the information used to prepare our December 31, 2013 reserve reports and other data in our possession or available from third parties. Our forward-looking estimates are also based on the completion of planned divestitures in the third quarter of 2014. Such statements are subject to a number of assumptions, risks and uncertainties, many of which are beyond our control.

Consequently, actual future results could differ materially from our expectations due to a number of factors, such as changes in the supply of and demand for oil, natural gas and NGLs and related products and services; exploration or drilling programs; political or regulatory events; general economic and financial market conditions; the timing of the transactions in the previous paragraph; and other risk factors we discuss in our Annual Report on Form 10-K. All subsequent written and oral forward-looking statements attributable to Devon, or persons acting on its behalf, are expressly qualified in their entirety by these cautionary statements. We assume no duty to update or revise our forward-looking statements based on new information, future events or otherwise.

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SIGNATURES

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

Date: August 6, 2014

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