If you purchased your iPhone within the past year or two, it’s likely to be unlocked, and free to use with any SIM. However, if your iPhone is older than that, it might be locked to a particular provider. That doesn’t mean you’re stuck with that provider forever, though.

You should be able to get your network to unlock your iPhone for you – often for free. In fact, you might even be able to unlock your iPhone yourself without ever needing to contact the original provider.

You’ll discover that your iPhone has been locked to a particular network if you insert a SIM card from another network into the iPhone and attempt to make a call. If it doesn’t work, it’s likely that your iPhone is locked to your network. You might see an error messages such as “Invalid SIM,” “PAYT Lock,” “SIM Card Not Accepted,” “Enter SP Code,” or “Insert Correct SIM Card.”

We have find this article in the internet and found very good for solving any iPhone locked problems.

It is easy to unlock your iPhone once you contact your carrier and net work provider.

EE (including Orange and T-Mobile) : If you’ve had your EE, Orange, or T-Mobile account for at least six months and have paid all of your bills to date, EE will unlock your iPhone for you. It’ll cost you £8.99 if you’re still within the contract though, and it could take up to seven days, which is not ideal.

Vodafone : Similarly, Vodafone requires you to have an account or know the details of the person who did. If those details are already available, you can go straight ahead and use Vodafone’s online unlocking form.

Three : You simply need to connect the iPhone to iTunes and restore the device to unlock it. You’ll want to back up your content first, though, as restoring it is going to wipe all of its data.

Alternatively, you can fill out Three’s online form.

O2: If your iPhone is locked to O2, you’ll be required to fill in an online form to unlock it. If you’re a Pay Monthly customer you can unlock your phone at any time, but you’ll still be required to finish paying for the rest of your contract.

Virgin Mobile: 

The good news is that all you’ll need to do is update your iPhone to iOS 8 or later and it’ll be unlocked for you.

If your iPhone isn’t compatible with iOS 8 – that is, if it’s an iPhone 4 or older – you’ll be able to perform a full restore of your iPhone to unlock it. Don’t forget to back up your data first, though.

Giffgaff:  Giffgaff has a handy tool that helps you figure out how to unlock your Apple iPhone from its network, which you’ll find here.

How to know if the unlock was successful

Once your phone has been unlocked you will receive a confirmation from the carrier. Now follow these steps:

  1. Power down the phone. Hold down the Sleep/Wake button and move your finger across.
  2. Use the SIM card tool (or a straightened paper clip) to eject the SIM card holder from the side of the phone.
  3. Remove the old SIM card from the SIM card holder. Place your new SIM card into the SIM card holder.
  4. Reinsert the SIM card holder into the iPhone.

How do I update an unlocked phone without the SIM card?

If you’ve requested an unlock from your carrier, but have not got the original SIM card, you will need to reset the phone before it will be unlocked. First, ensure that you have requested an unlock from the carrier. Now follow these steps

  1. Back up your iPhone. Either using Backup (Settings > iCloud > Storage & Backup > Back Up Now) or by connecting the iPhone to a computer and Using iTunes to perform a backup.
  2. Erase your iPhone. Click on Settings > General > Reset > Erase All Content and Settings.
  3. Complete the setup assistant and restore from your backup.

The phone should now be unlocked.

When you turn the iPhone back on, complete the setup assistant and restore it from the backup you created. Then you can insert the new SIM card and it should now work. So there you have it, your iPhone is unlocked!