Unlocking a O2 UK iPhone 4 for t mobile USA


macrumors member
Original poster
Aug 21, 2011
My brother lives in the UK and hes visiting us for a month here in Puerto Rico (we have a t mobile USA micro sim for him that is currently activated on a samsung galaxy S). He would like to use the iphone here instead. (yes he knows he will get EDGE speeds)

He has an iphone with the latest baseband (ends in 0.8) and ios 5.

A friend gave me a gevey sim for him and I heard I needed to downgrade the baseband (to end in 0.1).

How do I do this? I've found mixed results googleing information on this, some claim its possible, others say it cant be done.

Thanks for the help guys! :)


macrumors G3
Jul 24, 2009
Wirelessly posted (Mozilla/5.0 (iPhone; CPU iPhone OS 5_0_1 like Mac OS X) AppleWebKit/534.46 (KHTML, like Gecko) Version/5.1 Mobile/9A405 Safari/7534.48.3)

He can unlock his phone before he leaves the uk for £15 it'll then be sim free


macrumors 6502a
Nov 22, 2010
Just get in touch with O2 and they'll unlock the iPhone for £15, that's what I did for my 3GS.
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