ATT guide: Its FREE if the phone is CLEAN has ACTIVE account.
1. Look up your iPhone’s IMEI number
Go to Settings, then “General,” then “About,” and you’ll find the IMEI number listed near the bottom. Write it down. If you’re on a family plan, you’ll also need the last four digits of the main account holder’s social security number.
2. Contact AT&T by phone, on the web or in person
Dial (800) 331-0500, or 611 from an AT&T phone, or visit the carrier’s online support page for Wireless Support Chat. When the system asks what phone number you’re calling about, you can give your current number even if you’re unlocking a different phone.
3. Tell AT&T you want to unlock your out-of-contract iPhone
Provide your IMEI number and be patient during the unlock process.. You’ll also have to provide an e-mail address, where AT&T sends the unlock instructions.
4. Wait for AT&T’s e-mail
The e-mail arrives a couple minutes after getting off the phone, but other users have reported much longer waits. PCWorld’s Ed Oswald was told to wait eight days, and an Apple Insider forum-goer was told to wait five to seven business days.
5. When the e-mail arrives, back up and restore your iPhone in iTunes
Open iTunes on a computer that’s connected to the Internet. Make sure your iPhone has an active SIM card in it, then plug it into iTunes. Sync it with iTunes, then right-click on the device under the “Devices” column on the left side of the screen, and click “Back Up.” Once that’s finished, right-click on the device and select “Restore from Backup.”
If all goes well, you should get the following message in iTunes: “Unlock Complete. Congratulations, your iPhone has been unlocked. To set up and sync this iPhone, click Continue.” At this point, you should be able to insert SIM cards from other carriers.
ATT guide: Its FREE if the phone is CLEAN has ACTIVE account.
1. Look up your iPhone’s IMEI number
Go to Settings, then “General,” then “About,” and you’ll find the IMEI number listed near the bottom. Write it down. If you’re on a family plan, you’ll also need the last four digits of the main account holder’s social security number.
2. Contact AT&T by phone, on the web or in person
Dial (800) 331-0500, or 611 from an AT&T phone, or visit the carrier’s online support page for Wireless Support Chat. When the system asks what phone number you’re calling about, you can give your current number even if you’re unlocking a different phone.
3. Tell AT&T you want to unlock your out-of-contract iPhone
Provide your IMEI number and be patient during the unlock process.. You’ll also have to provide an e-mail address, where AT&T sends the unlock instructions.
4. Wait for AT&T’s e-mail
The e-mail arrives a couple minutes after getting off the phone, but other users have reported much longer waits. PCWorld’s Ed Oswald was told to wait eight days, and an Apple Insider forum-goer was told to wait five to seven business days.
5. When the e-mail arrives, back up and restore your iPhone in iTunes
Open iTunes on a computer that’s connected to the Internet. Make sure your iPhone has an active SIM card in it, then plug it into iTunes. Sync it with iTunes, then right-click on the device under the “Devices” column on the left side of the screen, and click “Back Up.” Once that’s finished, right-click on the device and select “Restore from Backup.”
If all goes well, you should get the following message in iTunes: “Unlock Complete. Congratulations, your iPhone has been unlocked. To set up and sync this iPhone, click Continue.” At this point, you should be able to insert SIM cards from other carriers.
http://techland.time.com/2012/04/11/unlock-an-att-iphone-in-5-easy-steps/