What is a PAC code?
A PAC (Porting Authorisation Code) is a unique code that authorises your new network to take over your existing phone number. Ofcom introduced the text-to-switch system in 2019, making it far simpler than the old process of calling your network and waiting days. You now get your PAC within 60 seconds by text, and your new provider handles the rest.
Before you switch: check coverage first
Switching network for coverage reasons is one of the most common reasons people use a PAC code — but it's easy to jump to a network that has the same gaps. Before requesting your PAC, check the coverage at your key locations: your home, your workplace, and any regular routes. Look specifically at indoor scores and 4G reliability, not just 5G, since 5G coverage is still incomplete in many areas.
The four-step switch process
Network-specific PAC guides
The process is identical across all UK networks — text PAC to 65075 — but each network has a different approach to early termination charges and retention offers. Here's what to expect:
Leaving EE
EE typically offers a retention deal if you call to cancel. If you're out of contract, there are no exit fees. In-contract customers pay the remaining monthly charges as a lump sum. EE will attempt to match a competitor's deal — only useful if you want to stay.
Leaving O2
O2 calculates early termination charges as the monthly line rental for the remaining months, minus a 3% discount. They're required to provide this figure in writing within five days of you requesting it under Ofcom rules.
Leaving Vodafone
Vodafone may offer price matching on retention calls. Early termination is charged at the remaining monthly fee — no discount. Vodafone's PAC is usually issued automatically via the 65075 text with no call required.
Leaving Three
Three charges early termination at the remaining contract value. Notably, Three's contract terms include a clause allowing you to exit without penalty if the network makes a price rise during your minimum term — worth checking if you've had a recent price increase.
MVNOs: which network are you actually on?
If you're on an MVNO like giffgaff, Sky Mobile, Tesco Mobile or iD Mobile, you're using a major network's infrastructure. Switching to the parent network directly won't improve your coverage — it uses the same masts. Check our guide to which networks use whose infrastructure to understand your options.
Frequently asked questions
Can I keep my existing number when switching?
Yes — that's exactly what a PAC code does. Text PAC to 65075 to get yours instantly. You must give it to your new provider within 30 days or it expires and you'll need to request a new one.
What if I'm still in contract?
You can request a PAC at any time, but leaving mid-contract usually incurs an early termination charge equivalent to the remaining months of your minimum term. Check your contract terms first — some networks waive it if coverage is demonstrably poor.
How long does the switch take?
Once you provide your PAC to your new network, the transfer completes by the end of the next working day. Some happen within hours. You'll receive a text confirmation when it's done.
What's a STAC code?
A STAC (Service Termination Authorisation Code) is used when you want to leave your current network without keeping your number. Text STAC to 75075. It works the same way as a PAC — valid for 30 days, free, received by text immediately.