Okay here it is... Boost unlimited now is soley advirtised under a the iden network which is also nextel that is gsn which has a sim card in the phone. Sprint is on a cdma network which is completly different and not compatible.... Boost does still have people on the cdma network but they are phasing out the phones so you would have to get a used one somewhere and have it activated on the cdma network. I have had no luck activating a sprint phone on boost cdma network they just wont do it