The phone has the ATT logo on it, so I can't imagine that it's that old. I called ATT and was told that ATT has always used SIM cards. But I took the back of the phone off and there just is nowhere to put a SIM card. Can anyone tell me if there is some other part of the phone that has to be opened to accept the card? Or is this phone too old to use with ATT? It doesn't make sense that it would be an ATT phone without a place for a SIM card. Thank you for your help!