How to Obtain the IMEI

Your first step before buying any used iPhone is to obtain the device’s IMEI number. The International Mobile Equipment Identity number serves as a unique identifier for a specific telecommunications device. If a secondhand seller refuses to disclose the IMEI, do not proceed with the sale. On an iPhone, visit Settings > General > About to view the IMEI.

Call Your Carrier

If you’re a customer of the wireless carrier, call the carrier to see if the iPhone is blocked on the network. Although this method isn’t perfect, odds are good that because networks align to radio types (CDMA versus GSM), your carrier will know if the device can be activated on its network.

Check the CTIA Database

Although it, too, isn’t perfect, the CTIA stolen-phone database is a pooled collection of stolen phone data. The major U.S. carriers consult it and contribute data to it. It’s only potential weakness is that a phone might not be reported stolen—for example, an old phone in a drawer pilfered by a thief.