UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

(Rule 14a-101)

INFORMATION REQUIRED IN PROXY STATEMENT

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

(Amendment No.    )

Filed by the Registrant  ☒                             Filed by a Party other than the Registrant  ☐

Check the appropriate box:

☐	Preliminary Proxy Statement
☐	Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))
☐	Definitive Proxy Statement
☒	Definitive Additional Materials
☐	Soliciting Material pursuant to § 240.14a-12

T-Mobile US, Inc.

(Name of Registrant as Specified In Its Charter)

N/A

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

☒	No fee required.
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☐	Check box if any part of the fee is offset as provided by Exchange Act Rule 0-11(a)(2) and identify the filing for which the offsetting fee was paid previously. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.
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***  Exercise Your Right to Vote  ***

Important Notice Regarding the Availability of Proxy Materials for the

Stockholder Meeting to Be Held on June 13, 2018.

T-MOBILE US, INC.		Meeting Information
		Meeting Type:            Annual Meeting
		For holders as of:      April 17, 2018
		Date:    June 13, 2018	Time:    8:00 A.M. PDT
		Location:  Four Seasons Hotel 99 Union Street Seattle, Washington 98101
		You are receiving this communication because you hold shares in the company named above.
	T-MOBILE US, INC. ATTN: MARC ROME 12920 SE 38TH STREET BELLEVUE, WA 98006	This is not a ballot. You cannot use this notice to vote these shares. This communication presents only an overview of the more complete proxy materials that are available to you on the Internet. You may view the proxy materials online at www.proxyvote.com or easily request a paper copy (see reverse side).
		We encourage you to access and review all of the important information contained in the proxy materials before voting.
		See the reverse side of this notice to obtain proxy materials and voting instructions.

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—  Before You Vote  —

How to Access the Proxy Materials

Proxy Materials Available to VIEW or RECEIVE: NOTICE AND PROXY STATEMENT          ANNUAL REPORT How to View Online: Have the information that is printed in the box marked by the arrow (located on the following page) and visit: www.proxyvote.com. How to Request and Receive a PAPER or E-MAIL Copy: If you want to receive a paper or e-mail copy of these documents, or proxy materials for future meetings, you must make a request. There is NO charge for such a request. Please choose one of the following methods to make your request:
1)	BY INTERNET:	www.proxyvote.com
2)	BY TELEPHONE:	1-800-579-1639
3)	BY E-MAIL*:	sendmaterial@proxyvote.com
*  If requesting materials by e-mail, please send a blank e-mail with the information that is printed in the box marked by the arrow (located on the following page) in the subject line. Requests, instructions and other inquiries sent to this e-mail address will NOT be forwarded to your investment advisor. Please make the request as instructed above on or before May 30, 2018 to facilitate timely delivery.

—  How To Vote  —

Please Choose One of the Following Voting Methods

Vote In Person: Many stockholder meetings have attendance requirements including, but not limited to, the possession of an attendance ticket issued by the entity holding the meeting. Please check the meeting materials for any special requirements for meeting attendance. At the meeting, you will need to request a ballot to vote these shares.

Vote By Internet: To vote now by Internet, go to www.proxyvote.com. Have the information that is printed in the box marked by the arrow (located on the following page) available and follow the instructions.

Vote By Telephone: You can vote by telephone by requesting a paper copy of the materials, which will include a proxy card with instructions.

Vote By Mail: You can vote by mail by requesting a paper copy of the materials, which will include a proxy card.

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Voting Items

The Board of Directors recommends you vote FOR the following:
1.	Election of Directors
	Nominees:
	01)	Thomas Dannenfeldt	07)	Thorsten Langheim
	02)	Srikant M. Datar	08)	John J. Legere
	03)	Lawrence H. Guffey	09)	G. Michael Sievert
	04)	Timotheus Höttges	10)	Olaf Swantee
	05)	Bruno Jacobfeuerborn	11)	Teresa A. Taylor
	06)	Raphael Kübler	12)	Kelvin R. Westbrook
The Board of Directors recommends you vote FOR proposals 2 and 3.
2.	Ratification of the Appointment of PricewaterhouseCoopers LLP as the Company’s Independent Registered public Accounting Firm for Fiscal Year 2018.
3.	Approval of an Amendment to the Company’s 2013 Omnibus Incentive Plan.
The Board of Directors recommends you vote AGAINST proposals 4 and 5.
4.	Stockholder Proposal for Implementation of Proxy Access.
5.	Stockholder Proposal for Limitations on Accelerated Vesting of Equity Awards in the Event of a Change of Control.
NOTE: Consider any other business that is properly brought before the Annual Meeting or any continuation, adjournment or postponement of the Annual Meeting.

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