Will my AT&T Galaxy S6 edge+ work in UK (Bought from AT&T in USA)?

[AC Question]

Phone will need to be unlocked (Once I pay it off), and I plan on cancelling AT&T and transitioning to a local provider in England. I believe It's GSM here in the states and CMDA overseas - will that be an issue?

 

[Rukbat]

It's GSM for AT&T and GSM for all of Europe. (If it were CDMA it wouldn't be a problem, you just couldn't use the phone there.) It might work on 4G with O2 or 3. It won't with EE or Vodaphone (different frequencies).