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Compare Three Mobile SIM only deals

Whether you want a cheap SIM deal, unlimited data or anything in between, Three Mobile is a fantastic choice, with fast 5G speeds at no extra cost.

Uswitch tips

How do I switch and keep my number?
Thumbnail, graphic - SIM cards from different networks. Uswitch compares deals from Lebara Mobile, O2, iD Mobile, Three, Vodafone and others.

1. Choose your new deal
Select a deal below and click through to the network’s site.

2. Get your PAC code
You’ll need a special code to keep your number when you switch. It's quick and free:
Text PAC to 65075 to receive your code.

3. Give the code to your new network
Contact the new network after signing up to provide them with your PAC code, which will begin the process and will automatically cancel your previous plan. Alternatively, you can enter the PAC code when signing up on the network’s site.

List of SIM Only deals

  1. Three Mobile SIM Deal

    Three Mobile

    £8.00 a monthMonthly cost will rise every April by £1.25.

    12 month contract

    40 GBof 5G data

    • Three+ rewards app
  2. Three Mobile SIM Deal

    Three Mobile

    £7.00 a monthMonthly cost will rise every April by £1.25.

    12 month contract

    30 GBof 5G data

    Black Friday
    • Three+ rewards app
  3. Three Mobile SIM Deal

    Three Mobile

    £10.00 a monthMonthly cost will rise every April by £1.50.

    12 month contract

    120 GBof 5G data

    Black Friday
    • Three+ rewards app
  4. Three Mobile SIM Deal

    Three Mobile

    £12.00 a monthMonthly cost will rise every April by £1.50.

    12 month contract

    120 GBof 5G data

    • Three+ rewards app
  5. Three Mobile SIM Deal

    Three Mobile

    £9.00 a monthMonthly cost will rise every April by £1.25.

    12 month contract

    60 GBof 5G data

    Black Friday
    • Three+ rewards app
  6. Three Mobile SIM Deal

    Three Mobile

    £12.00 a month

    No contract

    100 GBof 5G data

    • Inclusive roaming
    • Three+ rewards app
  7. Three Mobile SIM Deal

    Three Mobile

    £5.00 a monthMonthly cost will rise every April by £1.00.

    12 month contract

    3 GBof 5G data

    • Three+ rewards app
  8. Three Mobile SIM Deal

    Three Mobile

    £14.00 a monthMonthly cost will rise every April by £1.50.

    12 month contract

    250 GBof 5G data

    Black Friday
    • Three+ rewards app
  9. Three Mobile SIM Deal

    Three Mobile

    £10.00 a monthMonthly cost will rise every April by £1.25.

    12 month contract

    30 GBof 5G data

    • Inclusive roaming
    • Three+ rewards app
  10. Three Mobile SIM Deal

    Three Mobile

    £5.00 a monthMonthly cost will rise every April by £1.00.

    24 month contract

    3 GBof 5G data

    • Three+ rewards app
Can't find what you're looking for?

Uswitch services are provided at no cost to you, but we may receive a commission from the companies we refer you to. If a deal is "promoted" on Uswitch's tables, then it has been lent additional visibility as a result of us securing exclusivity on a great deal, or a commercial agreement to showcase what we believe to be market-leading value to consumers. Learn more about how our site works.

Please note: Mobile networks may increase monthly prices in line with the retail or consumer price index each year during the length of your contract. Please refer to individual network's terms and conditions before signing up.

Author: Nick Baker | Last updated: 25 July 2024

Our best Three Mobile SIMs

At Uswitch, we have a wide range of excellent SIM only deals on Three Mobile. You can sign up for as little as £5 a month and enjoy plenty of data, as well as unlimited calls and texts. 

Three Mobile offers a huge variety of keenly-priced SIM only deals, ranging from 3GB a month, all the way up to unlimited data. With any of these deals, you’ll be able to enjoy 5G speeds at no extra cost, provided your handset is 5G-compatible. So, if you’re ready to start shopping for a new Three Mobile SIM deal, scroll up to the top of this page and start comparing our best deals.

Why choose a Three Mobile SIM

  • 5G speeds at no extra cost

  • Uswitch award winner for Best Network for Data 2022

  • SIM only deals from £5 a month


  • You have to pay extra to use your SIM in the EU 

  • Most SIM only contracts last for 12 months

Is Three Mobile a good network?

Three Mobile is an excellent network. It’s one of the four big networks in the UK and it has its own network that offers 99% 3G and 4G coverage.  Even better, Three’s award-winning 5G network has now been rolled out across 400 towns and cities across the UK and is continuing to grow all the time.

As a Three Mobile customer, you’ll get access to lots of great perks, including the Three+ loyalty app, which is full of excellent offers. You can enjoy 20% off Uber Eats and £3 Cineworld tickets, as well as exclusive pre-sale tickets for gigs and events.

Three Mobile also has a helpful customer support team. They’re available Monday-Friday, 8am-10pm and 9am-6pm at weekends.

Three customers on Pay Monthly plans can get in touch by calling 333, free from their mobile phone. Alternatively, you can call 0333 338 1001 from any other phone and will be charged at their standard rate.

What network does Three Mobile use?

Three Mobile is one of the four major mobile phone network providers in the UK, so it uses its own network. As such, it’s able to deliver 3G and 4G coverage across 98.9% of the UK population. And its growing 5G network is now available in over 400 towns and cities.

Want a Three Mobile phone contract instead?

Take a look at our best pay monthly deals from Three Mobile today.

Compare Three mobile phone deals

Can I use my Three Mobile SIM abroad?

Yes, you can use your Three Mobile SIM when travelling. However, depending on where you’re going, you’ll probably have to pay extra for the privilege of doing so. Three is one of the many networks that have reintroduced EU roaming charges after Brexit, so you’ll be charged to use your Three SIM anywhere in the EU.

To find out more, check out our guide on Three international roaming charges.

What happens at the end of a Three Mobile SIM only contract?

When you’re nearing the end of your Three Mobile contract, Three will contact you to let you know when you’ll be able to switch to another deal. While you can continue on the same contract, it’s a good idea to shop around to see if there’s a better deal out there for you. Three Mobile will probably recommend a selection of deals. But since upgrade options direct from a network are usually on the pricier side, we’d recommend comparing SIM only deals to make sure you’re getting good value for money.

Can I keep my mobile phone number if I switch to a Three Mobile SIM only deal?

Yes, if you’re with a different provider, you’ll be able to transfer your number across to your new SIM only contract with Three Mobile. Once you’re ready to switch, all you need to do is text PAC to 65075 and you’ll receive a text with your PAC code. 

When you receive your Three SIM through the post, you’ll find instructions on how to give your PAC code to your new network. Three will then transfer your number across to your new phone.

If you want any additional information, check out our guide on how to switch mobile phone providers.

FAQs

Is Three’s 5G good?

Three Mobile’s 5G speeds are among the fastest in the country. And, as it’s now been rolled out across more than 400 towns and cities across the UK, more and more people are able to enjoy fast 5G with Three.

How do I cancel my Three SIM only contract?

When you’re ready to cancel your Three SIM only contract, you can do so by phoning 333 from your Three SIM and notifying them that you want to cancel your contract. You will need to give 30 days’ notice and you may need to pay an early exit fee if your contract hasn’t expired.

Are Three SIM only deals cheaper than mobile phone contracts?

Yes, generally speaking, SIM only deals are almost always cheaper than mobile phone contracts because you’re only paying for the usage without having to pay off the cost of a handset as well. So if you’re happy to continue using your existing handset, you could save a lot of money by opting for a SIM only deal instead.

Do I need an unlocked phone to use a Three SIM?

Yes, if you’re putting your Three SIM into a handset that hasn’t been provided by Three, you’ll need to make sure that it’s unlocked. If your mobile phone is locked, the easiest thing to do is call your current network to ask them to unlock it. To find out more, read our detailed guide on how to unlock your mobile phone.