Murphy USA Inc.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

(Rule 14a-101)

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

(Amendment No. )

Filed by the Registrantx

Filed by a Party other than the Registranto

Check the appropriate box:

Murphy USA Inc.

(Name of Registrant as Specified in Its Charter)

DEAR STOCKHOLDER:The Board of Directors and management cordially invite you to attend Murphy USA’s Annual Meeting of Stockholders to be held at 8:00 a.m., Central Time, on Thursday, May 7, 2026 at Murphy USA’s corporate headquarters, 200 East Peach Street, El Dorado, Arkansas 71730. The formal notice of the Annual Meeting of Stockholders and Proxy Statement follow.Whether or not you attend the Annual Meeting, it is important that your shares are represented and voted before or at the meeting. Therefore, we urge you to vote promptly and submit your proxy via the internet, by phone, or by signing, dating, and returning the enclosed proxy card. If you attend the Annual Meeting, you can vote in person, even if you have previously submitted your proxy.

ON BEHALF OF THE BOARD OF DIRECTORS, WEWOULD LIKE TO EXPRESS OUR APPRECIATIONFOR YOUR INVESTMENT IN MURPHY USA.

Sincerely,

R. Madison MurphyChairman of the Board of DirectorsMurphy USA Inc.March 26, 2026

NOTICE OF ANNUAL MEETING

The Annual Meeting of Stockholders of Murphy USA Inc. (the “Company”) will be held at Murphy USA’s corporate headquarters, 200 East Peach Street, El Dorado, Arkansas 71730, on Thursday, May 7, 2026, at 8:00 a.m., Central Time, for the following purposes:

1. Election of four Class I directors whose current terms expire on the date of the 2026 Annual Meeting;

2. Ratification of the action of the Audit Committee of the Board of Directors in appointing KPMG LLP as the Company’s independent registered public accounting firm for fiscal 2026;

3. Approval of executive compensation on an advisory, non-binding basis;

4. Amend the Certificate of Incorporation to phase-out the classification of the Board of Directors and provide for the annual election of directors;

5. Amend the Certificate of Incorporation to enable adoption of stockholders' right to call special meetings of stockholders;

6. If properly presented at the 2026 Annual Meeting, one stockholder proposal; and

7. Such other business as may properly come before the meeting by or at the direction of the Board of Directors.

Only stockholders of record at the close of business on March 9, 2026, the record date fixed by the Board of Directors of the Company, will be entitled to notice of and to vote at the meeting.

Cast Your Vote Right Away

It is very important that you vote. Please cast your vote right away on all of the proposals listed above to ensure that your shares are represented. For specific instructions on how to vote your shares, please refer to the instructions on the Notice of Internet Availability of Proxy Materials (“Notice”) you received in the mail or, if you requested to receive printed proxy materials, on your enclosed proxy card or voting instruction form.

Notice and Access

Important Notice Regarding the Availability of Proxy Materials for the 2026 Annual Stockholder Meeting To Be Held on May 7, 2026: This Notice of the 2026 Annual Meeting, the 2026 Proxy Statement and the 2025 Annual Report on Form 10-K are available, free of charge, at www.proxyvote.com.

We will be furnishing proxy materials over the internet to a number of our stockholders under the U.S. Securities and Exchange Commission’s (“SEC”) notice and access rules. Many of our stockholders will receive the Notice in the mail instead of a paper copy of this Proxy Statement, a proxy card or voting instruction card and our 2025 Annual Report. We believe that this process will reduce the environmental impact of our Annual Meeting as well as reduce the costs of printing and distributing our proxy materials. The Notice will instruct you as to how you may access and review all of the proxy materials on the internet.

All stockholders who do not receive the Notice will receive a paper copy of the proxy materials and our 2025 Annual Report by mail, unless they have previously elected to receive proxy materials by email. We remind stockholders who receive the Notice that the Notice is not itself a proxy card and should not be returned with voting instructions. The Notice only presents an overview of the more complete proxy materials. Stockholders should review the proxy materials before voting.

The Notice contains instructions on how to access our proxy materials and vote over the internet at www.proxyvote.com and how stockholders may receive a paper copy of our proxy materials, including this Proxy Statement, a proxy card or voting instruction card and our 2025 Annual Report. Atwww.proxyvote.com, stockholders may also request to receive future proxy materials in printed form by mail or electronically by email.

By the Order of the Board of Directors.

El Dorado, Arkansas

March 26, 2026