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Help & Support


Swapping your SIM card

Swapping your number onto a new SIM card

SIM swap is when you swap your current number onto a new SIM.

You might need a SIM swap for the following reasons:

  • You’ve got a new phone and your current SIM doesn’t fit in the new phone
  • You’ve lost your phone
  • Your current SIM is faulty or damaged

If your current SIM still works here’s how to SIM swap:
From your current SIM card, text SWAP to 23424. You’ll be sent some easy instructions to follow, which you can also check out by viewing our FAQs below.

If your current SIM doesn’t work or it’s been lost you’ll need to Call us to complete the SIM swap.

Do you need to change your SIM if you’ve upgraded to a new phone?

If your new phone takes a different sized SIM you’ll need to keep the new SIM in your new device and do your SIM swap.

If your new phone takes the same SIM card size as your current SIM card, you don’t need to do a SIM swap. Just take your current SIM card and put it in your new phone.

You may need to SIM swap if you’ve changed your phone or SIM card

If you have got a new phone from a family member or you’ve bought another phone from somewhere else, you will need to do a SIM swap if your new phone requires a different sized SIM card from your current one, if you need a new SIM please contact us to request one.

You’ll need a new SIM if your old SIM was lost or damaged and you don’t have your old SIM card

If your phone or SIM has been lost or stolen, please call us straight away on 0345 301 4455 and we will put a block on your SIM card and phone. We’ll also arrange for a new SIM to be sent out to you free of charge, and we’ll send this first class for delivery on the next working day. If you don’t have access to another phone, you can contact us online or via Facebook or Twitter.

If you’re a business customer, please contact us.

What do I need to do before I do my SIM Swap?

Make sure to transfer any data stored on your SIM that you want to keep on to the phone. Any data on the SIM like your contacts won’t be transferred to your new SIM. Not sure how to transfer your data? Follow the steps in our device support guide

How do I swap my SIM?
  • Text SWAP to 23424 from your original SIM card
  • You’ll receive a reply from us, asking for your new SIM Serial number (SSN). Standard and Micro SIMS are 19 digits, and Nano SIMS are 13 digits
  • If the SSN you’ve sent us is incorrect, we’ll send you another message, asking you to re-enter.
  • Once the details are accepted the SIM swap will be completed within 24 hours
  • If for any reason there is an error during the SIM swap, we’ll be in touch.
How long will my SIM Swap take?

The SIM transfer will take up to 24 hours. You’ll know it’s taking place when your old SIM loses signal. When this happens, put your new SIM in your phone and turn it off and on again to complete the transfer.

Can I put my current SIM into a 5G phone?

Yes, all of our SIM cards are ready to use in all our phones, including 5G phones. You’ll just need to be on a 5G tariff and have 5G coverage in your area to be able to enjoy the faster speeds of 5G.