There are some thousands questions on this and the IMEI has to be clean plus if it is indeed locked, ATT will have to "let it go."
So the answer to the question is maybe. There are plenty of online unlock offers that will do anything for the sale. Me? I just buy unlocked as I don't want to pay again for the unlocking or deal with a phone that the carrier won't let go.
I want to upgrade my phone. I currently have a Lg Stylo on Cricket and enjoy having a prepaid plan. I want to buy a Galaxy s6 edge from Gazelle but i see a difference in unlocked and locked prices. If i were to buy a locked AT&T phone, will i be able to unlock it? what are the steps i have to do ? Or will it just be easier to spend a little more to get an unlocked phone?

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