T-Mobile to Host Q4 & Full Year 2014 Earnings Call on February 19, 2015

February 12, 2015

Bellevue, Washington — February 13, 2015 — T-Mobile US, Inc. (NYSE: TMUS) will host a 90-minute earnings call and an extended, open conversation about the company’s financial and operational results for the fourth quarter and full-year 2014 on Thursday, February 19, 2015 from 9:00 a.m. to 10:30 a.m. Eastern Standard Time (EST). T-Mobile continues its mission to change the wireless industry and is applying its Un-carrier approach to quarterly reporting. Scripted remarks will be kept to a minimum in order to provide more time for free-flowing dialogue with analysts, investors, media and consumers.

Participants will have multiple ways to submit questions including via phone and Twitter (@TMobileIR using #TMUSearnings). This quarter, T-Mobile will also take questions via SMS and respond to some of them on the call (send a text message to 313131, enter the keyword TMUSQA followed by a space).

The embedded livestream on Twitter will have live-streamed video that can be accessed via a mobile device or desktop computer.

T-Mobile US, Inc. will issue a press release and Investor Factbook reporting its results at approximately 6:00 a.m. EST on Thursday, February 19, 2015. The press release and Investor Factbook will be posted at the same time on the Investor Relations website at http://investor.t-mobile.com.

Q4 and Full-Year 2014 Earnings Call, Livestream and Webcast Access Information

Access via Phone (audio only):

Date: Thursday, February 19, 2015

Time: 9:00 a.m. (EST)

Call-in Numbers: 800-432-9830

International: 719-234-7318

Participant Passcode: 9780158

Please plan on accessing the earnings call ten minutes prior to the scheduled start time.

Access via Social Media:

Embedded livestream on Twitter handle: @TMobileIR

Submit Questions via SMS Text or Twitter:

SMS Text: Send a text message to 313131, enter the keyword TMUSQA followed by a space

Twitter: Send a tweet to @TMobileIR using #TMUSearnings

Access via Webcast:

The earnings call will be broadcast live via the Company's Investor Relations website at http://investor.t-mobile.com. A replay of the earnings call will be available for two weeks starting shortly after the call concludes and can be accessed by dialing 888-203-1112 (toll free) or 719-457-0820 (international). The passcode required to listen to the replay is 9780158.

To automatically receive T-Mobile financial news by e-mail, please visit the T-Mobile Investor Relations website, http://investor.t-mobile.com, and subscribe to E-mail Alerts.

T-Mobile Social Media

Investors and others should note that we announce material financial and operational information to our investors using our investor relations website, press releases, SEC filings and public conference calls and webcasts. The company also intends to use @TMobileIR and @JohnLegere, which Mr. Legere uses as a means for personal communications and observations, as means of disclosing information about the company and its services and for complying with its disclosure obligations under Regulation FD. The information we post through these social media channels may be deemed material. Accordingly, investors should monitor these social media channels in addition to following the company’s press releases, SEC filings and public conference calls and webcasts. The social media channels that the Company intends to use as a means of disclosing the information described above may be updated from time to time as listed on the company’s investor relations website.

About T-Mobile US, Inc.

As America's Un-carrier, T-Mobile US, Inc. (NYSE: TMUS) is redefining the way consumers and businesses buy wireless services through leading product and service innovation. The Company's advanced nationwide 4G LTE network delivers outstanding wireless experiences to more than 55 million customers who are unwilling to compromise on quality and value. Based in Bellevue, Washington, T-Mobile US provides services through its subsidiaries and operates its flagship brands, T-Mobile and MetroPCS. For more information, please visit http://www.T-Mobile.com.

Investor Relations Contacts:

Nils Paellmann, Vice President, Investor Relations

212-358-3210 or 877-281-TMUS



Media Contacts:

T-Mobile US Media Relations