Don't know if this is posted or not so if it is then here's a reminder
02 Will give you an unlock code to unlock your iphone to all networks.
From 10 November, the iPhone can be unlocked for O2 customers in the UK.
Pay Monthly customers
Your iPhone can be unlocked at anytime free of charge. If you unlock your handset and place a non-O2 sim into it, you will still have to honour the remainder of the minimum term on your contract.
iPhone Pay & Go customers
Yes, you can unlock your iPhone for a one-off cost of £15. You'll pay for this from the money topped-up on your phone.
But if you unlock your iPhone less than 12 months after you bought it, we'll take off the free Web & Wi-Fi Bolt On (that we added for the first 12 months). You can buy a Web & Wi-Fi Bolt On for £10 a month when you fill in the unlocking form. Find out more about the Web & Wi-Fi Bolt On here.
What do I need to do?
Firstly, complete the unlocking form - it will take up to 14 days for the iPhone to be unlocked and we'll text you to confirm the unlock request. Then place a non-O2 sim into the iPhone and connect to iTunes via a USB cable. iTunes will confirm that the iPhone has been successfully unlocked.