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Switching Guide Updated September 2026

Leaving Three: the complete switching guide

PAC code in one text, exit fees explained, coverage checks and every way to reach Three — plus cheaper routes to great signal.

Leaving Three is simpler than it sounds: there are two ways out depending on whether you want to keep your number, and the whole thing can be done by text. This guide covers the PAC code, exit fees, how to check coverage on your next network, and every way to reach Three customer service if you get stuck.

1. Keep your number: get your Three PAC code

Text PAC to 65075 free from your Three SIM. Your code arrives by text within minutes, along with a breakdown of any early-exit charge — requesting the code commits you to nothing.

  • By text: PAC to 65075 (free, instant, valid 30 days)
  • In the app: the Three app has a switching/PAC option under account settings
  • By phone: call 333 free from your Three mobile

Give the code to your new network when you order or activate. The switch (and any exit fee) only triggers then — your number typically transfers within one working day.

Expired code? PACs last 30 days. Text PAC to 65075 again for a fresh one. On PAYG, unused credit doesn’t transfer — ask Three for a refund after switching.

2. Don’t need the number? Use a STAC code

Text STAC to 75075 instead. Give it to your new network and your Three contract cancels within one working day — same fee-transparent process as a PAC, no phone call required.

3. Cancelling without switching

If you’re not moving to another UK network, call 333 free from your Three mobile, or 0333 338 1001 from any other phone and give 30 days’ notice. You keep service until the notice period ends. The Three app also has a “leave” or “end my plan” option.

Early termination fees: mid-contract exit fees are typically your remaining monthly payments, reduced slightly since Three gets the money early. The exact figure arrives automatically in the PAC/STAC reply text — always request the code first so you see the real number before deciding. On a device plan, cancelling airtime doesn’t clear the remaining handset balance — check both.

4. Check coverage on your next network first

Three claims 99% 4G outdoor population coverage. Three and Vodafone merged in 2025 to form VodafoneThree — Three now runs on the combined “Nation’s Network”, which is gradually filling coverage gaps. But national averages don’t matter — what matters is the signal at your postcode.

  • Official checker: three.co.uk/support/network-and-coverage/coverage — 4G and 5G availability plus live status (Three switched off 3G entirely); the same page includes a live network status checker.
  • Independent check: Ofcom’s coverage checker at checker.ofcom.org.uk compares all four networks at the same address.
  • The definitive test: ask a friend on the network you’re considering (or an MVNO on it — Smarty and iD Mobile all share it) to check their signal at your home. Or order a free SIM and test for a week before moving your number.

5. What to switch to

Cheaper routes onto the Three network include Smarty and iD Mobile. But check whether O2 or Vodafone coverage is just as strong at your postcode first — if so, a free Giffgaff or Lebara SIM could undercut them further.

Both are free to test: order the SIM, check your signal for a week, then move your number with a PAC code.

Compare giffgaff vs Lebara side by side · or answer 3 questions for a recommendation

6. Three customer service — every route

If you need Three while you’re still a customer (final bill, PAC problem, exit-fee dispute), here are all the contact routes. Lines open Mon–Fri 8am–8pm, weekends 9am–6pm (live chat later: Mon–Fri 8am–10pm, weekends 9am–8pm).

RouteDetails
Phone333 free from Three mobile · 0333 338 1001 other phones
Live chatthree.co.uk contact page — open later than the phone lines
AppThree app — bills, allowances, upgrades, add-ons
SocialThree on X and Facebook during opening hours

Complaints: ask for your issue to be logged as a formal complaint — Three publishes a complaints code of practice. If it’s unresolved after 6 weeks (or you get a deadlock letter sooner), escalate free to the Communications Ombudsman.

Important: don’t let Three close your account before your number has moved — that loses the number permanently. The PAC process handles the closure automatically once your new network uses the code.