How to Use an Unlocked Cell on AT&T
- 1). Purchase a SIM card from AT&T Wireless. You can purchase pre- and postpaid SIM cards online from AT&T. Alternatively, you can purchase SIM cards in person at any AT&T retail store or service center. A prepaid SIM card allows you to use your unlocked phone with AT&T's prepaid calling services. Prepaid calling services require no credit check or contract. A postpaid SIM card requires a credit check and a one or two year service contract.
- 2). Insert an active AT&T SIM card into the unlocked cell phone. In most cases, you can find the SIM card holder under the phone's battery. Remove the back cover and battery from the phone. Remove any existing SIM card and insert the AT&T SIM card. If you can't find your phone's SIM card holder, check your phone's operating instructions for details about how to locate it.
- 3). Re-insert the phone's battery and replace the back cover. Power on your phone.
- 4). Look at your phone's display. Once the AT&T logo appears in the upper-right corner of the display, you can use your phone on AT&T's cellular network. It can take up to five minutes for the AT&T logo to appear after powering on the phone.
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