How do you know if the phone you have has been reported stolen?

Every cell phone sold in the US since the eary '80's has what is called an ESN (Electronic Serial Number). This is used in programing the phone to the system on which it runs (the provider). If the phone you have was stolen, in theory, it would not be possible for you to connect to any provider in the US. Mistakes happen though. If you are turly curious, you can contact any service provider and ask them to check the "Bandit List." This is an industry term for the national list of stolen phone ESN's. If your phone was stolen and reported, its ESN will be on that list.