Factory unlocking an AT&T iPhone 4, 4s or 5 models will let you use your handset with other wireless carriers. The unlocking process does nothing but let the device to be off-contract. In general, you are automatically off-contract after using the iPhone with AT&T for 2 consecutive years. However, to get out of the contract even earlier there is an early termination fee. Remember that your account has to be in good standing to be eligible for a factory unlock, meaning that none of your payments should be due. An unlocked iPhone will be marked in the official IMEI database as unlocked.
Switching to local wireless carriers when you travel abroad proves to be cheaper. Otherwise, you need to pay for the international coverage of AT&T. However, the new carrier has to be GSM supported, the CDMA carriers such as Sprint or Verizon Wireless won’t work with an unlocked iPhone.
Below, I have tried to list down the exact steps that you need to undergo for unlocking an AT&T iPhone via IMEI:
Looking Up the IMEI Number
Go to Settings->General->About, right at the bottom of your screen, you should be able to locate the IMEI number. You should also make a note of the last 4 digits of the main account holder’s SSN.
Contacting Support Team of AT&T
There are two ways of contacting the support team of AT&T: you can visit the official support page or dial 611 from your AT&T phone. The support team may ask various questions during the unlocking process and you need to answer all of their queries patiently. The information that you have noted in the previous step will be required now. You may also need to provide them an email id where the detailed unlocking instructions will be sent.
Backup and Restore iPhone in iTunes
In general, you need to wait for 5 to 7 business days for receiving an email from AT&T support team. It will contain detailed instructions to unlock the iPhone. You need to open iTunes on a computer which is connected to the internet. The iPhone must have an active SIM card inserted and upon verifying that, you need to plug it into iTunes. Sync it and then click on the Back Up button.
Once backup is completed, select the Restore from Backup option. If you have done everything correctly, you should receive a confirmation message stating that your iPhone has been successfully unlocked. Right at this point, you can insert SIM cards from other carriers into your iPhone.
The process of iPhone unlocking can seem to be intimidating to those who have never done it before. To help them with it, there are plenty of reputable services like Keys2iPhone which officially unlock the iPhone. They charge a small fee; however, you are spared of all the hassle. If you wish to know more, see here how to quickly unlock iPhone 4.
One of the most common questions people ask about iPhone unlocking (based on the Keys2iPhone blog post) is whether they can unlock their At&t iPhone to work with T-Mobile SIM. The short answer: it depends on the iPhone model. iPhones 4, 4s will work just fine. If you bought your iPhone 5 in Canada or U.S., it will work fine on T-Mobile LTE network but not on all HSPA+ bandwidths. Check your model number – it must be the A1428, sold by AT&T, the Canadian operators or Apple for it to work on all T-Mobile networks. All of these devices must be unlocked, though, or they’ll be blocked.
