UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 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): June 4, 2013

T-MOBILE US, INC.

(Exact Name of Registrant as Specified in Charter)

Registrant’s telephone number, including area code: (425) 378-4000

(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:

Approval of the T-Mobile US, Inc. 2013 Omnibus Incentive Plan

At the Annual Meeting of Stockholders (the “Annual Meeting”) of T-Mobile US, Inc. (the “Company”) held on June 4, 2013, the Company’s stockholders approved the T-Mobile US, Inc. 2013 Omnibus Incentive Plan (the “2013 Plan”). The 2013 Plan was adopted by the Company’s board of directors (the “Board”) on May 1, 2013, subject to stockholder approval.

The 2013 Plan authorizes the issuance of up to an aggregate maximum of 63,275,000 shares of the Company’s common stock, subject to adjustment as described in the 2013 Plan, as well as up to 11,471,996 shares of common stock (the number of such shares as of May 8, 2013), subject to adjustment as described in the 2013 Plan, that were subject to outstanding awards under the Company’s predecessor equity plans on the date of stockholder approval of the 2013 Plan that subsequently cease to be subject to such awards (other than by reason of exercise or settlement of the awards in shares).

The 2013 Plan may be administered by the Board, or by a committee appointed by the Board or such committee’s delegate (each referred to as the “Committee”). The Committee, in its discretion, selects the individuals to whom awards may be granted, the time or times at which such awards are granted, and the terms of such awards. The 2013 Plan authorizes the Committee to grant stock options, stock appreciation rights, restricted stock, restricted stock units, other stock based awards, and performance awards that may be denominated in stock or cash and may be paid in stock or cash. Awards may be granted to the Company’s officers, employees, consultants and advisors of the Company and its affiliates and to non-employee directors. Unless earlier terminated by the Board, the 2013 Plan will terminate, and no further awards may be granted, after June 4, 2023.

The material features of the 2013 Plan are described in our definitive proxy statement for the Annual Meeting filed with the Securities and Exchange Commission on May 17, 2013, and amended on May 28, 2013, entitled “Proposal 3—Approval of the T-Mobile US, Inc. 2013 Omnibus Incentive Plan,” which description, as amended, is filed as Exhibit 99.1 with this Form 8-K and incorporated herein by reference. The description of the 2013 Plan is qualified in its entirety by reference to the copy of the full text of the 2013 Plan, which is filed as Exhibit 10.1 to this Form 8-K.

As discussed in Item 5.02 above, the Company held the Annual Meeting on June 4, 2013, after notice was duly given and at which a quorum of the Company’s stockholders was represented by proxy or in person. At the Annual Meeting the following three proposals were presented:

Proposal 1 - Election of Directors

The following eleven directors were elected at the Annual Meeting to serve terms ending at the Company’s 2014 Annual Meeting of Stockholders, or until their successors are elected and qualified, unless the director earlier resigns, retires, passes away or otherwise no longer serves as a director:

Proposal 2 - Ratification of the Appointment of PricewaterhouseCoopers LLP

The stockholders ratified the appointment of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for the Company’s fiscal year 2013 as follows:

Proposal 3 - Approval of the T-Mobile US, Inc. 2013 Omnibus Incentive Plan

The stockholders approved the T-Mobile US, Inc. 2013 Omnibus Incentive Plan as follows:

(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.

Date: June 4, 2013

EXHIBIT INDEX