AT&T Inc. is the largest provider of fixed telephony in the United States and is also a provider of broadband and subscription television services. As of 2010[update], AT&T is the 7th largest company in the United States by total revenue, as well as the 4th largest non-oil company in the US (behind Walmart, General Electric, and Bank of America).

It is the 3rd largest company in Texas by total revenue (behind ExxonMobil and ConocoPhillips) and the largest non-oil company in Texas. It is also the largest company headquartered in Dallas. In 2011, Forbes listed AT&T as the 14th largest company in the world by market value, and the 9th largest non-oil company in the world by market value. It is the 20th largest mobile telecom operator in the world with over 96 million mobile customers.

Southwestern Bell Corporation was one of seven Regional Bell Operating Company that was incorporated in 1983 by AT&T Corp following the break-up of the original AT&T as a result of the United States v. AT&T antitrust suit. The company changed its name in 1995 to SBC Communications Inc. and again in 2005 to AT&T Inc. after it purchased its former parent company, AT&T Corporation. The newly merged company took on the iconic AT&T logo and stock-trading symbol (NYSE: T, for "telephone").