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How to activate an AT&T phone or tablet?

Activating your AT&T device is easy, simply follow these steps and you’ll be up and running in no time. 

Note: Your device must be unlocked from your previous carrier networks to activate it on AT&T’s network.

  • After you’ve verified your phone is unlocked, AT&T recommends that you perform a data backup by transferring information such as contacts, photos, and videos.
  • If you purchased an AT&T SIM Card from an online market retailer, you’ll want to find the correct SIM card size for your device.
  • If you’re new to AT&T, you’ll need a new AT&T SIM card which you’ll need to order. You can make this purchase online or in-store.
  • Once you’ve got the SIM Card in your hand, it’s time to insert the SIM Card in your device.
  • Insert your new SIM card in your phone or device, restart your device, and you're ready to go.
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