What Is a STAC Code? Switching Without Cancelling
What Is a STAC Code?
A STAC code (Service Termination Authorisation Code) is a code that lets you transfer your mobile phone number to a new network without automatically cancelling your old contract. It gives you the flexibility to keep your existing plan running while you settle into a new provider.
How STAC Differs from PAC
The key difference is what happens to your old contract:
| Feature | PAC Code | STAC Code |
|---|---|---|
| Text to | 65075 | 75075 |
| Keeps your number | Yes | Yes |
| Old contract | Cancelled automatically | Stays active — you cancel separately |
| Early termination fee | May apply immediately | Only when you cancel the old contract |
| Best for | Clean switch to new network | Keeping old contract running temporarily |
When to Use a STAC Code
A STAC code is useful in specific situations:
- Using up remaining allowance — if your old contract has data, minutes or texts you want to use before cancelling
- Keeping a second SIM active — for example, a work and personal number on different networks
- Waiting for contract end date — porting your number now but cancelling the old contract when the minimum term expires to avoid early termination fees
- Testing a new network — trying the new provider before fully committing to cancellation
How to Get a STAC Code
Text STAC to 75075 from your mobile phone. Like PAC codes, Ofcom requires your network to provide the STAC within 1 minute by text message. The code is free to request and valid for 30 days.
Important: Cancel Your Old Contract Separately
This is the most critical thing to understand about STAC codes. When you use a STAC to port your number, your old contract does not cancel. It continues running and you will continue to be billed. You must contact your old provider directly to cancel.
If you forget to cancel, you could end up paying two contracts simultaneously — your old plan (now without your number) and your new plan. Set a reminder to cancel your old contract as soon as your number has ported successfully.
Should You Use PAC or STAC?
Most people should use a PAC code. It is the simpler option — your number moves and your old contract ends in one step. Only choose a STAC code if you have a specific reason to keep your old contract active, such as the scenarios listed above.
- Want a clean switch? Text PAC to 65075
- Need to keep your old contract? Text STAC to 75075
For more detail on PAC codes and the full switching process, see our PAC code guide.
