SIM Lock PIN code
When enabling SIM Lock on your device, your device will prompt you to enter the PIN:
The default PIN for an AT&T SIM card is 1111. For additional security, you can change this PIN code.
When you enable SIM Lock, the security option follows the SIM card if the card is moved from one device to another.
For instructions to enable SIM Lock, consult your device's User Manual. To download a copy, visit the Device How-To center and select User Guide.
PUK code
If the SIM Unlock PIN code is entered incorrectly three times, the SIM card will lock, and you will need to get a PUK (PIN Unlock Key) code from to unlock your SIM card.
To get a PUK code for your GoPhone, call 611 from your GoPhone or 800.901.9878 from any phone.
For all other wireless customers, you can get the PUK code online by following these steps:
Select myAT&T at the top of the page. If prompted, log in. Don't have a myAT&T login? Register today!
At the top of the page, hover over Wireless, and then select My Phone / Device.
If necessary, click Select and choose the mobile number that needs the PUK code.
Under Manage my phone/device, select the Unlock SIM card using PIN Unlock link.
On the Unlock SIM Card Using PIN Unlock Key screen, view your PUK code and follow the instructions for unlocking your SIM Card.
Important Note
If your device displays PUK blocked call operator or PUK2, your SIM is permanently locked because the wrong PUK code was entered 10 times in a row. You'll need to get a new SIM from an AT&T Retail Store or by calling us at 800.331.0500 or 611 from your AT&T wireless phone.