Some stores and web sites will perform that task for a fee, sometimes $30. But Jailbreak Wizz offers to unlock almost any AT&T phone for free.
The service uses an app called Free AT&T Unlock Mobile that checks the phone’s IMIE number and provides an unlock code. Getting the unlock code takes a few days but reviews posted on the app’s download page indicate that the company keeps users updated on its progress through regular emails.
The company has a long list of brands and models that can be unlocked with its service. The list includes all phones from popular brands such as Apple, Samsung LG and HTC plus more obscure brands such as Sonic, Pantech and ZTE.
For more details, check out the app listing in the Google Play Store and the FAQ page on the Jailbreak Wizz website.