does AT&T wireless use sim cards and if so do they fit T-mobile phones?

[cojane3000]

I want to get a blackjack because they aren't available at t-mobile but i like the features

 

[3 cheers 4 sweet revenge]

yes and yes and those sim cards save your life

 

[ifilmu]

dpendns on the phone you have AT&T operate with 2 different frequncies you need to see what frequecie they both operate on

 

[Bama Gurl]

yes to both.