A:Answer Yes, I bought this and just put my old SIM in and worked great - didn't have to let T-mobile know I changed. It show this phone on the website now......Just make sure all the phone numbers, etc are saved to your SIM and not your phone.....I lost one or 2 contacts. A rep at T-Mobile suggested buying a prepaid phone because I wanted a flip phone and didn't wanna pay them like 80.00