If you signed up for new AT&T service or received a promotion card for upgrading your current services, you must activate the card before you can use it. Several options exist for activating a promotion card from AT&T, including online and over the phone.
To activate your AT&T promotion card online, visit the Promotion Card activation page. Enter the card's first 10 digits and the activation Personal Identification Number code. Your PIN code is the last four digits of your AT&T wireless number.
Over the Phone
AT&T offers the option to activate over the phone, as well. Call the toll-free number on the back of the promotion card and follow the voice prompts. You'll need the card's first 10 digits as well as your PIN code.
You can use the promotion card anywhere Visa is accepted, but you cannot use it for cash withdrawal. To use the card to pay for gas, do not pay at the pump. Instead, see the gas station attendant to make your purchase.
Each promotion card has an expiration date, usually 150 days from the date of issue.