How to Activate an AT&T GoPhone SIM Card Online

By Vera Leigh

Activiate your Go Phone on AT&T's website.
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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."

Step 1

Visit the official AT&T phone activation website.

Step 2

Locate your SIM card number on the credit-card-like card included with your Go Phone.

Step 3

Type the SIM number, which begins with the number "89," into the SIM Card Number box.

Step 4

Press "Continue."

Step 5

Select a payment plan for your Go Phone, process your payment, and finalize activation. You are ready to talk on your Go Phone.