AT&T Mobility, LLC, also known as AT&T Wireless and marketed as simply AT&T, is an American telecommunications company. It is a wholly owned subsidiary of AT&T Inc. and provides wireless services in the United States. AT&T Mobility is the largest wireless carrier in the United States, with 241.5 million subscribers as of December 31, 2023.

T-Mobile US, Inc., often shortened as T-Mobile, is an American wireless network operator headquartered in Bellevue, Washington, U.S. Its largest shareholder is multinational telecommunications company Deutsche Telekom AG, a German company headquartered in Bonn, Germany. As of April 2023, the European company holds a 51.4% majority stake in the company. T-Mobile US is the third-largest wireless carrier in the United States, with 117.9 million subscribers as of December 31, 2023.