iPhone 4 and 4S

[kids]

Firstly you need to complete the unlock request form http://campaigns.vodafone.co.uk/UnlockCodeRequestForm/

Vodafone (VF) ask Apple to unlock the phone, Apple then change the phone’s details on their database to show it is unlocked. Once Apple have processed the unlock request the next time you connect the phone to iTunes you will get a message in iTunes that the phone is now unlocked. The message will also ask you to insert a sim from a different network to the one the phone was locked to which will complete the unlocking. Only the original owner of the phone (unless it is a PAYG phone) can request the unlocking 

Once the unlocking request has been accepted by Vodafone it can take up to seven working days for Apple to process the unlock

If the phone is PAYG there is a charge of £19.99 otherwise it is FOC

[Nabs]

Hi David,

If you are a paymonthly customer:

You need to copmlete this form

After a few days Apple should have unlocked your handset and you will need to connect it to iTunes with your new SIM installed so it can download the new netwrok settings

If you are a PAYG customer then you will need to ensure you have at least £20 of credit and you will need to contact customer services.

More details can be found here