T-mobile US Inc — Current Report (Form 8-K)

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 31, 2026

T-MOBILE US, INC.

(Exact Name of Registrant as Specified in its 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:

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

On March 31, 2026, following the previous repayment of certain legacy indebtedness, T-Mobile USA, Inc. (“TMUSA”), a wholly-owned subsidiary of T-Mobile US, Inc. (“TMUS”), elected to release the guarantees of certain subsidiaries under its $10 billion revolving credit agreement pursuant to the terms thereof, resulting in a corresponding release under the indentures dated April 28, 2013, April 9, 2020 and September 15, 2022, governing its outstanding senior notes. As a result, following the release, the obligors under TMUSA’s revolving credit agreement and outstanding senior notes now consist of TMUSA, as issuer or borrower, and each of TMUS, Sprint LLC, Sprint Capital Corporation and Sprint Communications LLC, as guarantors. Corresponding subsidiary guarantor releases were also effected under other TMUSA debt facilities, including its export credit agency facilities and unsecured short-term commercial paper program.

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 hereunto duly authorized.