FLEXIBLE PREPAID SIM CARD OPTIONS: The H2O Wireless prepaid SIM card is preloaded and triple-cut to fit Standard, Micro, and Nano sizes, ensuring compatibility with your 4G (minimum) GSM-unlocked ...

You can activate your AT&T SIM in-store, online, or by contacting customer service. The process is similar for postpaid and AT&T prepaid customers.

Prepaid wireless service providers in the United States have become increasingly competitive in recent years as they evolve offerings to be more on par with post-paid service features and plans. For ...