When a handset is locked, it'll only work with the network that it was bought it from. In order to take advantage of the SMARTY plans, you may need to unlock your device.
How can I tell if a phone is locked?
Just insert a friend's SIM from another network (from your current provider) into your phone and see if it works. If it does, your phone is unlocked. If it doesn't, then your handset needs unlocking.
You may also see a prompt asking you to enter SIM Network Unlock PIN.
How do I unlock my phone?
You've got 2 options.
You could take your phone to an independent phone shop on the high street and they'll charge about £15 to unlock it.
But we'd recommend calling your old mobile provider and asking them to help. Every network has the ability to unlock a phone, but some networks do charge a fee for this.
How long does it take to unlock a phone?
The time needed to unlock a phone depends on the network processing the change.
Some networks will unlock a phone straight away, while others may take a bit longer. In some cases, the unlocking process could take up to 30 days.
Is it illegal to unlock a phone?
No, you're perfectly entitled to unlock your handset. Just be aware that you do risk invalidating your warranty when you do so.