Now, it has been confirmed that units of Apple iPhone 5 that were purchased for full price from AT&T (off-contract) can be unlocked through a simple iTunes reset very easily. If it is unlocked, you can use GSM networks like T-Mobile and others.
Usually, the process of unlocking an AT&T iPhone is a long process. Users have to fill out a form online, send AT&T a fax, and then waiting 5 to 7 days while it processes. But it is not the case with the AT&T iPhone 5 owners who bought their phone off-contract only. Instead of a lengthy process, users only need the easy one-step process via iTunes and get unlocked message after restoring it successfully.
After receiving the confirmation message, you can confirm that your Apple iPhone 5 is unlocked and you can use GSM-Compatible Nano-SIM instead of AT&T Nano-SIM in your iPhone 5.
After receiving the notification that your Apple iPhone 5 was unlocked, you can cut a micro-SIM card into the shape of a nano-SIM. We had already posted the DIY guide on how to cut your SIM to Nano SIM in an easy way.
Unfortunately, If you buy into a two-year contract for the subsidized starting price of $200, you usually can’t unlock it until you’ve fulfilled your contract.