How to Activate an AT&T GoPhone SIM Card Onlineby Vera Leigh
If you have purchased an AT&T Go Phone, then you will need to activate it in order to begin using it. You can activate your Go Phone online by visiting the official AT&T phone activation site. Make sure to have your SIM card number handy. The official site reports that you will find your SIM card number on the plastic credit card-like card included with your phone. The SIM number begins with the number "89."
Visit the official AT&T phone activation website.
Locate your SIM card number on the credit-card-like card included with your Go Phone.
Type the SIM number, which begins with the number "89," into the SIM Card Number box.
Select a payment plan for your Go Phone, process your payment, and finalize activation. You are ready to talk on your Go Phone.