I am hoping someone might know the answer to my question. I use T-Mobile for my cell phone, and have done so for the last 8 years. I do not currently have a contract with them, and would prefer not to sign one. My phone has recently decided to stop functioning correctly, so I have to get a new one. Now, I am able to get an upgraded phone with them, but it would require signing a two year contract. I know most of their phones (if not all of them) use SIM cards. Is it possible for me to buy a T-Mobile phone off Ebay (or something similar) and simply put my sim card into it? Are there any ramifications of doing this? I simply want a phone that will function properly, but don't want to sign a contract or pay tons of money for it.