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April 7, 2017

What Do I Do If My Phone Has A Bad ESN?

If you’re buying a used cell phone, watch out, because you might get more than you bargained for.There are two types of cellular networks used around the world. GMS (AT&T and T-Mobile), which uses SIM cards to identify individual phones; and CDMA (Verizon and Sprint), which uses ESNs. ESN stands for Electronic Serial Number, and it functions just like any other serial number.Carriers use phone ESNs to identify specific phones and blacklist those that have been stolen. ESNs might be “bad,” which means the carrier has blacklisted the phone. So if your phone is blacklisted, where does this leave you? What can you do about it?

Why Would an ESN Be Bad?

Cellular carriers flag an ESN as bad if the phone is reported lost or stolen. They’ll also flag it if the previous account holder has an outstanding balance. Reputable dealers will check with an ESN service before they sell the phone, but phones bought from private sellers are sometimes reported stolen after the sale.

How Do I Know If My Phone ESN is Bad?

If you’re suspicious of your phone ESN, you can verify it online. ESN numbers are found on the back of the phone by the battery, or in the phone’s settings. If an ESN service can’t find anything wrong, try calling the carrier directly. They may not give you information about the account, but they can tell you if a hold was placed and why.

My Phone Has a Bad ESN - What Now?

Once you’ve confirmed that the phone ESN is bad, your next step is contacting the seller. Most reputable dealers, even online (such as Amazon or eBay), have policies protecting consumers. If your seller was an individual, they may not know the phone has a balance and that they can settle it themselves. However, if your ESN is bad and the seller isn’t cooperative, you still have other options.


ESN numbers flagged for account non-payment are still usable by other carriers. Most carriers are happy to “flash” your phone, or reregister the ESN to themselves rather than the old service provider. Many carriers do this at their stores for a fee. But note that carriers will not flash phones flagged as lost or stolen.

What if the Phone was Reported Stolen?

If the phone was reported stolen, your only option is to use the phone without cellular capabilities. Phones can also be used as fancy MP3 players, or to play games. However if you do come into possession of a stolen phone, try your best to return the phone to its owner.When buying a used cell phone, it’s good to know about ESNs and how to check them. Between stolen phones and late bill payments, there’s a number of ways to get an ESN blacklisted.But even so, if the ESN on your new phone is bad, all is not lost. Refer back to our article and refresh yourself on what to do if your phone has a bad ESN.

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