Could I unlock my iphone 4 at the T-Mobile store?

My Iphone contract recently ended and I want to get a sim only contract with a different provider but its locked to T-mobile, If I go into the store could they unlock my phone for me someone was telling me they will but they charge? Does anyone know for sure?

They will unlock it but they will not necessarily be able to do it on the day, they need to take the IME number from the phone and go through Apple to unlock it which can take days.

Some networks will do it free once the contract has been paid but some charge, all except EE provide the service and currently T Mobile are listed as charging £15.32 and taking 28 days on this website, it is the giffgaff website but the advice and information here applies to anyone looking to get their phone unlocked.

http://giffgaff.com/unlock/apple-iphone-4-phone