[Skip to content](https://www.t-mobile.com/news/press/t-mobile-us-expands-board-of-directors-and-names-coo-mike-to#maincontent) [Newsroom](https://www.t-mobile.com/news)Toggle secondary navigation - [Network](https://www.t-mobile.com/news/category/network) - [Devices](https://www.t-mobile.com/news/category/devices) - [Un-carrier](https://www.t-mobile.com/news/category/un-carrier) - [Community](https://www.t-mobile.com/news/category/community) - [Offers](https://www.t-mobile.com/news/category/offers) - [Business](https://www.t-mobile.com/news/category/business) English [Press Release](https://www.t-mobile.com/news/press) # T‑Mobile US expands Board of Directors and names COO Mike Sievert to Board February 23, 2018  2 min read - Facebook IconShare on Facebook - Share on Twitter - LinkedIn IconShare on LinkedIn __Bellevue, Washington — February 22, 2018 —__ T‑Mobile US (NASDAQ: TMUS) has named Mike Sievert, Chief Operating Officer, to its Board of Directors. Sievert joined T‑Mobile as Executive Vice President and Chief Marketing Officer in 2012 before moving to his current role as Chief Operating Officer in 2015. As COO, Sievert leads T‑Mobile’s customer-facing operations across the business, including its award-winning customer care team, retail management and sales organization, marketing, product management, business planning, T‑Mobile For Business and Layer3 TV. “Mike’s been instrumental to the Un-carrier’s success, and I know he’ll be a great addition to our Board of Directors,” said John Legere, CEO and president of T‑Mobile. Sievert is one of the architects of T‑Mobile’s Un-carrier movement to change wireless for good. He has been instrumental in the company’s charge to build a nimble business focused on fixing customer pain points, an approach that has been the foundation for T‑Mobile’s unprecedented growth over the past five years. Sievert’s appointment increases the size of the Board from eleven to twelve directors. \# # #   About T‑Mobile US, Inc. As America's Un-carrier, T‑Mobile US, Inc. (NASDAQ: TMUS) is redefining the way consumers and businesses buy wireless services through leading product and service innovation. Our advanced nationwide 4G LTE network delivers outstanding wireless experiences to 72.6 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 [https://www.t‑mobile.com](https://www.t-mobile.com/).   __T‑Mobile Media Contacts__ T‑Mobile US Media Relations [MediaRelations@t‑mobile.com](mailto:MediaRelations@T-Mobile.com)   __T‑Mobile Investor Relations__  877-281-TMUS OR 212-358-3210  [investor.relations@t‑mobile.com](mailto:investor.relations@t-mobile.com)  Mike Sievert, COO of T‑Mobile US, Inc.. Link to view and download the [asset](https://www.t-mobile.com/content/t-mobile/corporate/news/media-library/details/image.html/content/dam/t-mobile/corporate/media-library/public/articles/2018/02/t-mobile-us-expands-board-of-directors-and-names-coo-mike-to/Mike%20CES2014_0664_upper%20crop.jpg) in the Media Library. Tags[Employees](https://www.t-mobile.com/news/archive/employees)[Un-carrier Inside](https://www.t-mobile.com/news/archive/un-carrier-inside) ## Related Stories [More Stories](https://www.t-mobile.com/news/stories) [ \ BusinessPress Release \ __T‑Mobile Declares Quarterly Cash Dividend__ \ June 15, 2026|1 min read](https://www.t-mobile.com/news/business/t-mobile-declares-q3-2026-cash-dividend) [ \ BusinessPress Release \ __T‑Mobile Delivers Continued Durable Postpaid Account and ARPA Growth, Translating to Best-in-Class Financial Growth, Raises Guidance__ \ April 28, 2026|17 min read](https://www.t-mobile.com/news/business/t-mobile-q1-2026-earnings) [ \ __T‑Mobile Fuels Small Businesses as they Grow__ \ April 16, 2026|6 min read](https://www.t-mobile.com/news/stories/t-mobile-fuels-small-businesses-as-they-grow) [ \ NetworkPress Release \ __On the Front Lines of Hurricane Preparedness: T‑Mobile at the National Hurricane Conference (Updated 4/1)__ \ March 31, 2026|4 min read](https://www.t-mobile.com/news/network/on-the-front-lines-of-hurricane-preparedness-t-mobile-at-the-national-hurricane-conference)