AT&T Inc.

T: The wireless business contributes about two thirds of AT&T's revenue following the spinoff of Warner Media. The firm is the third-largest U.S. wireless carrier, connecting 70 million postpaid and 18 million prepaid phone customers. Fixed-line enterprise services, which account for about 18% of revenue, include internet access, private networking, security, voice, and wholesale network capacity. Residential fixed-line services, about 11% of revenue, primarily consist of broadband internet access service. AT&T also has a sizable presence in Mexico, serving 22 million customers, but this business only accounts for 3% of revenue. The firm still holds a 70% equity stake in satellite television provider DirecTV but does not consolidate this business in its financial statements.