Verified against Ofcom Connected Nations Spring 2026, Opensignal April 2026 reports and current operator tariffs.
Quick answer: A STAC code (Service Termination Authorisation Code) is a 6-digit code your current UK mobile network sends you so you can switch to a new provider without keeping your phone number. Text STAC to 75075 from any UK mobile — your network must reply within one minute. Once you give the STAC to your new provider, the switch happens within one working day and your old contract is cancelled automatically.
What is a STAC code?
STAC stands for Service Termination Authorisation Code. It is the official Ofcom-mandated mechanism for leaving your mobile network when you do not want to keep your number. Before STAC codes were introduced in 2019, you had to phone customer service, listen to retention pitches and request termination manually. Now you can do it via a single text — and your old network is forced to cancel within one working day, with no early termination fees applied for the days you have already used in your final billing month.
STAC code vs PAC code — what’s the difference?
| Feature | STAC code | PAC code |
|---|---|---|
| Use it when… | You want to switch and get a new number | You want to switch and keep your number |
| Text to get one | STAC to 75075 | PAC to 65075 |
| Network reply time | ≤ 1 minute | ≤ 1 minute |
| Validity | 30 days | 30 days |
| Switch completes within | 1 working day | 1 working day |
| Old contract cancelled? | Yes, automatically | Yes, automatically |
If you are unsure, get a PAC if you ever use that number for work, banking, 2FA or contacts. Get a STAC only when you are happy to lose the number. Need a PAC instead? See our PAC code guide.
How to get a STAC code from any UK network
Text STAC
From your current UK mobile, text the word STAC to 75075.
Receive the code
Within 1 minute you’ll get a 6-digit STAC plus your termination charges (if any).
Pass to new provider
Give the STAC to your new network at sign-up — phone, web or in-store.
Switch in 1 working day
Your old SIM stops working. New SIM activates with a new number.
That is the whole process. The text-to-75075 system is universal across EE, Vodafone, O2 / VM O2, Three, Voxi, giffgaff, Smarty, Tesco Mobile, Sky Mobile, BT Mobile and every other UK MVNO. It is mandatory under Ofcom’s General Conditions.
Switching mobile networks for your business?
We handle STAC, PAC, porting, provisioning and number management for you across all four UK networks.
What is in the STAC code message?
When you text STAC to 75075 you’ll receive a single SMS containing:
- The 6-digit STAC code itself.
- Any early termination fee (ETF) — the cost of leaving your contract early, if applicable.
- Outstanding handset balance if you bought your phone on a split contract.
- Final bill date — when your last invoice will be issued.
- Any pay-as-you-go credit balance that will be lost.
Read it carefully before you give the STAC to a new provider. If the ETF is high, sometimes waiting to the natural end of your minimum term is worth it.
STAC code vs cancelling — when to use which
Use a STAC if…
You’re moving to a new mobile network and don’t need to keep your old number. Saves a retention call.
Use a PAC if…
You want to keep the same number on a new network. Same process, different code.
Just cancel if…
You’re leaving the mobile world entirely and won’t be taking up a new contract. Call your provider directly.
Don’t switch if…
The early termination fee is over £200 and you’ve less than 4 months left. Run out the contract and switch then.
Switching network? Get a better deal
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How long is a STAC code valid?
Thirty days from issue. After 30 days it expires and you’ll need to text 75075 again. Most switches complete within 24–48 hours of the new provider receiving the code, so 30 days is plenty.
Common STAC code mistakes to avoid
- Giving a STAC when you meant to give a PAC. Once the switch completes you cannot recover the old number. Always double-check.
- Letting it expire. If you don’t use the STAC within 30 days you have to start over.
- Switching mid-billing-cycle without checking ETF. A 6-month early termination on £40/month means £240 ETF — sometimes worth waiting.
- Not paying off handset balance. If you bought the phone on a split contract, the handset finance does not disappear when you switch — you still owe the device portion.
- Forgetting 2FA / banking accounts tied to the number. If your bank, HMRC or work systems use the old number for SMS 2FA, update them before you trigger the STAC.
Can a business STAC multiple SIMs at once?
Yes — but the text-to-75075 method is per-SIM and cumbersome at scale. For business fleets:
- EE Business: Bulk termination via the EE Business Hub or your account manager.
- Vodafone Business: Bulk STAC requests via the Vodafone Business Portal.
- O2 / VM O2: Email account manager with the SIM list and effective date.
- Three Business: Through your account manager or the Three Business app for accounts under 25 SIMs.
If you are switching a fleet to a new supplier, an authorised business mobile partner like Connection Technologies can coordinate the STAC and provisioning end-to-end so there is no service gap.
Frequently asked questions
FAQs about STAC codes
If you’re switching networks because your current plan no longer fits the team, our updated guide to the best business mobile phone plans in the UK compares EE, O2, Three and Vodafone with real per-line pricing.
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