T-Mobile Announces Full Exercise of Underwriters’ Option to Purchase Common Stock

T-Mobile US, Inc. (NYSE: TMUS) (“T-Mobile”) announced that the underwriters of its previously announced public offering have exercised in full their option to purchase an additional 6,615,000 shares of T-Mobile’s common stock at a price to the public of $25.00 per share, less underwriting discounts and commissions. Including the exercise of the underwriters’ option to purchase additional shares, the net proceeds to T-Mobile are expected to be approximately $1.8 billion, after deducting underwriting discounts and commissions, and other estimated offering expenses payable by T-Mobile. T-Mobile expects to use the net proceeds from this offering for general corporate purposes, including capital investments, enhancing its financial flexibility and opportunistically acquiring additional spectrum in private party transactions and/or government auctions.

Morgan Stanley & Co. LLC, Goldman, Sachs & Co., J.P. Morgan Securities LLC, Credit Suisse Securities (USA) LLC and Deutsche Bank Securities Inc. are the joint book-running managers for the offering.

The offering is being made pursuant to an effective shelf registration statement filed with the Securities and Exchange Commission (“SEC”), which became effective November 7, 2013. Copies of the prospectus supplement and the accompanying prospectus related to the offering may be obtained by contacting: Morgan Stanley & Co. LLC, 180 Varick Street, 2nd Floor, New York, New York 10014, Attention: Prospectus Department, or by calling (866) 718-1649, or by emailing prospectus@morganstanley.com; Goldman, Sachs & Co., Attention: Prospectus Department, 200 West Street, New York, New York 10282, telephone: 1-866-471-2526, or email: prospectus-ny@ny.email.gs.com; J.P. Morgan Securities LLC, c/o Broadridge Financial Solutions, 1155 Long Island Avenue, Edgewood, New York 11717, telephone: (866) 803-9204; Credit Suisse, Prospectus Department, One Madison Ave., New York, NY 10010, telephone: 1-800-221-1037, or email: newyork.prospectus@credit-suisse.com; or Deutsche Bank Securities Inc., Attention: Prospectus Group, 60 Wall Street, New York, New York 10005-2836, by telephone at +1 (800) 503-4611 or by email at prospectus.cpdg@db.com.

This press release does not constitute an offer to sell or the solicitation of an offer to buy, nor shall there be any sale of, these securities in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualifications under the securities laws of any such state or other jurisdiction.

Cautionary Language Regarding Forward-Looking Statements

This press release contains forward-looking statements that are based on T-Mobile management’s current expectations. Such statements include, without limitation, plans, projections and estimates regarding the use of proceeds from the proposed offering. Such forward-looking statements are subject to certain risks, uncertainties and assumptions, including, without limitation, prevailing market conditions and other factors. Should one or more of these risks or uncertainties materialize, or should underlying assumptions prove incorrect, actual results may vary materially from those expected. More information about potential risk factors that could affect T-Mobile and its results is included in T-Mobile’s filings with the SEC, which are available at http://www.sec.gov.