I am on ATT, I had an ol razor i wanted to sell to a guy on tmobile, i called ATT and asked for the unlock code, they emailed it to me in 3 days, and this phone was not even activated, so if you already have service with somebody just call and ask, i was surprised it was so easy with ATT, the unlock code is detrmined by that IMIE code thats by the battery, Att claims they email motorola and motorola sends it to them,,,, anyway mine was free,, good luck