PAC code: how to keep your mobile number when you switch network (UK guide)
A PAC code lets you take your UK mobile number with you when you change network. You get it by text in minutes, the switch takes one working day, and it is free. This guide covers the whole process, including STAC codes for leaving without your number.
What a PAC code is
PAC stands for Porting Authorisation Code. It is a nine-character code (three letters and six digits) that your current network gives you so a new network can take over your number. Under Ofcom’s rules every UK mobile network must issue one on request, free of charge, and must not try to talk you out of it first. The code is valid for 30 days. If you do not use it in that time it expires and you simply ask for another.
You can port any UK mobile number (071–075 and 077–079 ranges) between any two UK networks, including the smaller brands that use the big networks (giffgaff, Lebara, Lyca, VOXI, SMARTY, Tesco Mobile and others). Landline and 070 numbers are not covered.
Get your PAC by text in two minutes
Since 2019 the fastest route is Ofcom’s text-to-switch service:
- From the phone with the number you want to keep, text PAC to 65075.
- Within a minute you receive the code by text, with any early-termination charge or outstanding balance shown alongside it.
- Keep the text. You will give the code to your new network.
Prefer another way? Log in to your network’s app or account page and look for “PAC” or “Keep my number”, or call customer services. Pay-as-you-go and contract customers can both ask. If you are on a business account, the account holder has to request it.
Give the code to your new network
Order your new SIM or plan first, then hand over the PAC:
- Online or in the app: most networks have a “Bring your number” page in the account area where you type the PAC and the number.
- By phone or in store: give the PAC, the number you are keeping and the temporary number on the new SIM.
The new network does the rest. Ask on a working day before about 5pm and the switch usually completes by the end of the next working day; a request on Friday afternoon lands on Monday or Tuesday. Keep both SIMs in use until the old one stops working, then put the new SIM in. If your new SIM is already in the phone, you may need to restart it once the port goes through.
What happens to your old contract
Using a PAC cancels your old plan automatically; you do not need to ring and cancel. Anything you owe still applies: if you are inside a minimum term, the early termination charge in the PAC text is what you will be billed. Pay-as-you-go credit on the old SIM is normally lost, so spend or transfer it first. Your handset is unaffected, as long as it is unlocked for the new network. If you are moving to a brand that runs on the same underlying network, the port still works and still takes a working day.
STAC: leaving without keeping your number
If you want to close your account but not keep the number, text STAC to 75075 instead. A Service Termination Authorisation Code works the same way: give it to the new network and the old account closes the next working day without a notice period. People use STAC when they are taking a new number, for example a memorable one bought on its own SIM, and want the old one gone cleanly.
Moving a number you bought to your own plan
If you have bought a memorable number from a dealer such as us, the number arrives live on its own UK pay-as-you-go SIM. To put it on your existing contract or SIM-only plan, the PAC is requested from the new SIM, not from your current phone:
- Put the new SIM in any phone and text PAC to 65075. The code arrives by text.
- Give that code to your current network and say you want the new number to replace the one on your account.
- Next working day, your plan continues as before, with the new number. Nothing else on the contract changes.
Your old number then expires with the old SIM. If you would rather keep both, run the new number as a second SIM instead and skip the PAC. Our buying guide explains both routes, and the FAQ covers what we post and when.
If the port stalls
- No PAC text back: make sure you texted from the SIM with the number you want to keep and that it has signal and a few pence of credit. Business SIMs often need the account holder to request it.
- “PAC invalid”: check the three letters and six digits, and that it is under 30 days old. Codes are case-insensitive.
- Still the old number after two working days: ring the new network; it owns the request. Ofcom’s rules allow a port to be chased and completed, and networks pay compensation if they cause delays.
- Switched but no calls: restart the phone and check the new SIM is set as the default for calls. Texts can take a few hours longer than calls to move.
If you bought the number from us and anything stalls, message us on WhatsApp with the number and the PAC and we will chase it with the network.
Quick answers
Is a PAC code free? Yes, always.
How long is it valid? 30 days.
How long does the switch take? By the end of the next working day after you give the code to the new network.
Can I keep my number if I owe money? Yes. The PAC still works; the balance is billed separately.
Can I move a number to the same network under a different brand? Yes, with a PAC, as a normal port.
What is the difference between PAC and STAC? PAC keeps your number; STAC closes the account and lets the number go.
Want a number worth keeping?
Thousands of memorable UK numbers in stock. Buy once, then move it to your network with the steps above.
