Can I use my t mobile sim card on a At&T cell phone?

[GoldenJ]

My t mobile phone broke today and I only have my old at&t phone left. Can I use the sim card on the at&t phone and will it work?

Please help.

 

[Joseph]

Not unless your AT&T phone is unlocked, which it most likely is not. Put it in, if you can make a call, then it works.

 

[saravedi]

@Golden....No without unlocking the AT&T phone from network lock.You can't use with other GSM Network Sim card like T-Mobile Sim...You can get the unlock code from the site Prounlocking and unlock it from network lock....Then use with T-Mobile Sim card.