October 10, 2018

John J. Legere
Chief Executive Officer and Director
T-Mobile US, Inc.
12920 SE 38th Street
Bellevue, WA 98006

       Re: T-Mobile US, Inc.
           Amendment No. 1 to
           Registration Statement on Form S-4
           Filed October 1, 2018
           File No. 333-226435

Dear Mr. Legere:

      We have reviewed your amended registration statement and have the
following
comments. In some of our comments, we may ask you to provide us with
information so we
may better understand your disclosure.

       Please respond to this letter by amending your registration statement
and providing the
requested information. If you do not believe our comments apply to your facts
and
circumstances or do not believe an amendment is appropriate, please tell us why
in your
response.

       After reviewing any amendment to your registration statement and the
information you
provide in response to these comments, we may have additional comments. Unless
we note
otherwise, our references to prior comments are to comments in our August 24,
2018 letter.

Amendment No. 1 to Registration Statement on Form S-4

Questions and Answers, page 5

1.     We note your response to prior comment 2. Please consider including a
new Q&A that
       explains why shareholders' consents of both companies are being
solicited when approval
       by both companies is assured due to Deutsche Telekom and Softbank's
intentions to
       approve the merger.
 John J. Legere
FirstNameUS, Inc.
T-Mobile LastNameJohn J. Legere
Comapany NameT-Mobile US, Inc.
October 10, 2018
October 10, 2018 Page 2
Page 2
FirstName LastName
Risk Factors
Failure to complete the merger could negatively impact T-Mobile and Sprint and
their respective
businesses..., page 45

2.       In your response to prior comment 1, you state that on a standalone
basis for each
         company, "Sprint's relative 5G strength will be significant capacity
where it offers 5G
         service, but its geographic coverage will be more limited, while
T-Mobile's relative
         strength will be very broad geographic coverage, but it will have more
limited capacity."
         Please include this disclosure in your filing in order to clarify both
companies' ability to
         compete effectively with Verizon and AT&T in providing 5G service
absent the merger.
The Merger Transactions, page 65

3.       We note your response to prior comment 9. Expand your disclosure to
explain in Plain
         English the "valid non-tax business and commercial reasons" for
utilizing the HoldCo
         mergers as part of the overall merger.
Unaudited Pro Forma Condensed Combined Financial Information
Note 5. Notes to Unaudited Pro Forma Condensed Combined Balance Sheet, page 253

4.       We note your response to prior comment 19 and the revisions to your
disclosure for
         adjustment 5(f). Since other market participants likely have different
cell site locations,
         projects or other property and equipment than you, it seems that your
fair value approach
         may incorporate entity specific assumptions. Notwithstanding your
specific plans for
         these assets, please tell us how your fair value estimates reflect the
highest and best use by
         market participants as described in ASC 805-20-30-6.
Note 6. Notes to Unaudited Pro Forma Condensed Combined Statements of
Operations, page
258

5.       Please revise your discussion of adjustment 6(c)(ii) to clarify, as
you describe in your
         response to prior comment 22, why you are reducing compensation
expense for the post-
         combination portion of Sprint's equity awards assumed by T-Mobile.
Material U.S. Federal Income Tax Consequences of the Merger, page 290

6.       We note that the receipt of a tax opinion that the merger will qualify
as a "reorganization"
         within the meaning of Section 368(a) of the Tax Code is predicated on
the HoldCo
         mergers being consummated. Confirm that an opinion of tax counsel will
be filed as an
         exhibit to the Form S-4 (which can assume that the HoldCo mergers are
consummated),
         and clarify what the expected tax consequences to shareholders will be
if the merger is
         consummated without the HoldCo mergers having occurred.
 John J. Legere
T-Mobile US, Inc.
October 10, 2018
Page 3

        You may contact Lisa Etheredge, Staff Accountant, at (202) 551-3424 or
Robert S.
Littlepage, Accountant Branch Chief, at (202) 551-3361 if you have questions
regarding
comments on the financial statements and related matters. Please contact Joshua
Shainess,
Attorney-Adviser, at (202) 551-7951 or Larry Spirgel, Assistant Director, at
(202) 551-3810 with
any other questions.



FirstName LastNameJohn J. Legere                           Sincerely,
Comapany NameT-Mobile US, Inc.
                                                           Division of
Corporation Finance
October 10, 2018 Page 3                                    Office of
Telecommunications
FirstName LastName