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 17, 2014

Exxon Mobil Corporation

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (972) 444-1000

(Former name or former address, if changed since last report)

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:

On March 17, 2014, Exxon Mobil Corporation (the “Company”) entered into an underwriting agreement (the “Underwriting Agreement”) with HSBC Securities (USA) Inc., J.P. Morgan Securities LLC and Morgan Stanley & Co. LLC, as managers of the several underwriters named therein, for the issuance and sale by the Company of (i) $750,000,000 aggregate principal amount of its Floating Rate Notes due 2017 (the “2017 Floating Rate Notes”), (ii) $500,000,000 aggregate principal amount of its Floating Rate Notes due 2019 (the “2019 Floating Rate Notes” and, together with the 2017 Floating Rate Notes, the “Floating Rate Notes”), (iii) $1,500,000,000 aggregate principal amount of its 0.921% Notes due 2017 (the “2017 Fixed Rate Notes”), (iv) $1,750,000,000 aggregate principal amount of its 1.819% Notes due 2019 (the “2019 Fixed Rate Notes”) and (v) $1,000,000,000 aggregate principal amount of its 3.176% Notes due 2024 (the “2024 Fixed Rate Notes” and, together with the 2017 Fixed Rate Notes and the 2019 Fixed Rate Notes, the “Fixed Rate Notes”).

On March 20, 2014, the Company entered into an indenture (the “Indenture”) with Deutsche Bank Trust Company Americas, as trustee. The Floating Rate Notes and the Fixed Rate Notes (together, the “Notes”) will be issued pursuant to the Indenture, as supplemented by an officer’s certificate (the “Officer’s Certificate”) dated March 20, 2014 establishing the terms and forms of the Notes.

The Notes were offered pursuant to the Company’s Registration Statement on Form S-3 filed with the Securities and Exchange Commission on March 17, 2014 (Reg. No. 333-194609) (the “Registration Statement”).

The Underwriting Agreement, the Indenture and the Officer’s Certificate (including the forms of the Notes) are filed as Exhibits 1.1, 4.1 and 4.2, respectively, to this current report on Form 8-K and are incorporated by reference into the Registration Statement. The opinions of Davis Polk & Wardwell LLP and James E. Parsons, Esq., Coordinator – Corporate Securities and Finance Law of Exxon Mobil Corporation, are filed as Exhibits 5.1 and 5.2, respectively, to this current report on Form 8-K and are incorporated by reference into the Registration Statement.

(d) Exhibits.

SIGNATURE

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 hereunto duly authorized.

INDEX TO EXHIBITS