AT&T Inc., an abbreviation of its predecessor's original name, the American Telephone and Telegraph Company, is an American multinational telecommunications conglomerate headquartered at the Whitacre Tower in Downtown Dallas, Texas. AT&T is the world’s third-largest telecommunications company by revenue, the third largest wireless carrier in the United States behind T-Mobile and Verizon, and the nation's biggest fiber internet provider. On the New York Stock Exchange, AT&T trades under the ticker symbol “T,” and has a market capitalization of $186.83 billion. On the Fortune 500 (2025) AT&T ranked 37th among the largest American businesses and reported revenues of $125.6 billion last year.
