How to Switch SIM Provider in the UK (2025 Guide)
Complete step-by-step guide to switching your mobile network provider while keeping your number. Fast, easy, and free.
5 min read
Switching your SIM provider in the UK is easier than ever. Here's everything you need to know to make the switch smoothly.
Why Switch SIM Providers?
The UK mobile market is competitive, with providers constantly offering better deals. You might switch to:
- Save money on your monthly bill - often £10-20/month
- Get more data for the same price
- Access better network coverage in your area
- Take advantage of promotional offers
Ready to get started?
Browse our hand-picked selection of the best UK SIM deals updated weekly
View Best Deals →Step-by-Step Switching Process
1. Find Your New Deal Browse <a href="/" class="text-primary hover:underline font-medium">current SIM-only deals</a> and choose the one that suits your needs. Not sure what you need? Check our <a href="/guides/how-to-choose-best-sim-deal" class="text-primary hover:underline font-medium">guide on choosing the best SIM deal</a>.
2. Request Your PAC Code A PAC (Porting Authorisation Code) lets you keep your existing phone number. To get yours: - Text "PAC" to 65075 from your current SIM - Call your current provider and request it - You'll receive it within 60 seconds via text
Learn more about PAC codes and how they work.
3. Order Your New SIM Purchase your chosen SIM-only deal. Most providers deliver within 2-3 working days, or you can collect from stores.
4. Provide Your PAC Code Give your PAC code to your new provider within 30 days. You can do this: - During online checkout - Through their app - By calling customer service
5. Activation Your new SIM will activate on the date you specify (usually next working day). Your old SIM stops working automatically when the new one activates.
Important Things to Know
You Won't Lose Your Number: The PAC code ensures your phone number transfers to your new provider.
No Service Interruption: The switch happens in minutes. Put your new SIM in once you receive confirmation.
Contract Obligations: If you're in a contract, you may face early termination fees. SIM-only deals are usually 30-day rolling contracts with no long-term commitment.
Network Coverage: Check your new provider's network coverage in your area before switching. We compare all UK networks to help you choose.
Ready to get started?
Ready to switch? Find your perfect SIM deal from top UK providers
View Best Deals →Common Questions
How long does switching take?
From requesting your PAC code to activation, the process takes 2-3 working days.
Will I lose my WhatsApp messages?
No. WhatsApp is tied to your phone number, which stays the same.
Can I switch if I'm in a contract?
Yes, but you may have to pay the remaining contract months as an early termination fee. Learn about SIM-only vs contract costs.
Do I need to unlock my phone?
Only if your phone is locked to your current network. Contact your provider to unlock it (usually free after contract ends).
Ready to Switch?
Check out our curated list of the best SIM-only deals to find your perfect match. All deals are regularly updated and we only show genuine value.
Popular choices for switchers:
- Smarty SIM deals - Great value on Three's network
- giffgaff plans - Reliable O2 coverage
- Unlimited data plans - For heavy users
Need help deciding? Read our complete guide to choosing the best SIM deal.
Ready to find your perfect SIM deal?
Browse our curated selection of the best UK SIM-only deals
View Current DealsMore Guides
What is a SIM-Only Deal? Complete UK Guide for 2025
Everything you need to know about SIM-only mobile plans. Learn how they work, who they're for, and how much you can save.
What is a PAC Code? UK Guide to Keeping Your Number
Complete guide to PAC codes in the UK. Learn how to get yours, use it to switch networks, and keep your mobile number.