Three SIM only deals

Our best Three SIMs this week

Compare Three SIM only plans

With generous data allowances at affordable prices, Three SIM only deals are an attractive option for Netflix bingers, Spotify streamers and avid gamers. While there are cheaper SIM-only deals out there from some smaller networks, Three is arguably the cheapest of the four main providers – the others being O2, Vodafone and EE.

Why choose a Three SIM?

• Good coverage: Three offers extensive 3G and 4G coverage, as well as a growing 5G network
• Above-average speeds: Three’s speeds are good, but they are beaten by the likes of EE and Vodafone
• Tethering: You can tether your phone on all Three SIM only plans
• Wi-Fi calling: On offer to all customers and allows them to call and text in the UK in locations with no mobile signal

Is Three a good network?

Three launched back in 2003 and is one of the four main networks. This means it operates its own infrastructure and does not depend on any other network for coverage quality. 

Three isn't quite as cheap as it once was. But there's a lot to recommend it. 

All of Three's plans come with unlimited calls and texts and are 5G ready, so you'll be able to experience fast mobile internet speeds for no extra cost

Sadly, Three got rid of its much loved Roam At Home offering, which saw roaming included with almost all of its plans. Since October 2021, you’ve had to pay £2 a day to unlock your allowance in Europe and £5 in other destinations around the world under its Go Roam tool.

Read our complete Three network review.

What to look for in a Three SIM contract

There are lots of options when it comes to SIM deals from Three. The most important things to look at are monthly allowances and price. It's critical to ensure you’re not paying for more data than you actually need.

We can help you find the best Three SIM deal with our comparison table.

Simply adjust the filters so you only see the most relevant deals for your requirements, sort them in the way you like and select the deal you like the look of. Click through to Three to sign up.

Compare Three with our best sim-only deals this week.

Cheap Three SIMs

Does Three offer SIM plans for bad credit?

You will have to pass a credit check to take a SIM plan out with Three. If you fail, you won’t be able to take out a Pay Monthly plan, but you can still join on pay-as-you-go.

12-month Three SIMs

There are many options for 12-month SIM deals on Three, and these are usually cheaper than 30-day ones. You can choose between Three’s Essential or Advanced plans.

Three SIMs with unlimited data

Three’s all-you-can-eat data tariffs mean you can watch, read, listen and play as much as you want online on your mobile, and not worry about being charged extra.

Unlimited data plans tend to be more expensive though, so make sure you actually use the amount of data you think you do, or you might end up paying for a contract you don’t really need.

Check out our guide on how much mobile data you really need.

Should I get unlimited calls and texts?

All Three SIM-only deals come with unlimited calls and texts.

Can I cancel my monthly plan whenever I want with a Three SIM only plan?

If you have a rolling monthly plan with Three, you can cancel at any time, with your allowance being available up until its next renewal date.

If you have a 12 month SIM plan with Three, then you will need to wait until it comes to its final month before you can cancel without charge. Cancelling ahead of that date will mean you have to pay an early exit fee, possibly as much as the entire value of the remaining contract. Keep this in mind if you want to lock yourself in for a year.

Which networks offer good SIM plan alternatives?

• O2
• EE
• Vodafone
• Giffgaff
• Tesco Mobile
• Virgin Mobile
• Talk Mobile
• Sky Mobile
• Plusnet
• iD Mobile
• VOXI
• SMARTY
• Lebara

Can I use my Three SIM abroad?

Three no longer offers inclusive roaming, meaning that you have to pay £2 a day to access your allowance in Europe, rising to £5 a day in other destinations. Known as Go Roam, this will automatically kick in when you make a call, send a text or go online.

Can I get 5G enabled Three SIMs?

Yes, all Three’s SIMs are now 5G ready. So as long as you have a 5G phone, you’re good to go.

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

Yes, it's almost always possible to keep your current phone number when you switch to a new network.

If you’re moving from another network, you’ll need to call them and request your PAC (porting authorisation code). You can also do this online or via text. You will need to provide this to Three who will move your number over.

If you are already a Three customer, they will port your number over for you.

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

Your phone does need to be unlocked to use a Three SIM card. The good news is that it’s easy to check whether your phone is locked by popping a friend or family’s SIM card (from a different provider to yours) into your phone.

If it works, then it’s unlocked. Otherwise you'll need to contact your current operator and ask them to unlock it for you.

Are Three SIM-only deals cheaper than contract?

Yes, SIM-only deals tend to be cheaper in the long run compared to phone-and-SIM contracts because you’re not paying back the cost of a handset.

Three do have some great contract deals though and the overall difference in cost for slightly older or less fancy phones is not much.  

If you'd rather not splash out on a handset upfront, a Three contract can give you all the same benefits as its SIM plans and make your costs more reasonable.

What is a PAC code?

A PAC (port authorisation code) is something you’ll need in order to cancel your existing deal and move your number to a new network. The process is now easier than ever, with all networks offering a text number so you can get your PAC immediately.

Give this to Three and it will arrange for the transfer right away. Be aware that if you're moving from a Three contract to SIM only, you may need a PAC. Call Three on 333 to check.

Can other people use my Three data using a personal hotspot?

Yes. By giving people access to your Three personal hotspot, they can share your data either on their phone, tablet or PC. Just remember that this will mean your connection will be slower and that it uses your data allowance up quickly.

Does Three offer SIM plans for bad credit?

Three carries out credit checks for all of its SIM plans. That means if you have bad credit, you may not be able to get a monthly deal. However, you can take advantage of some excellent, affordable PAYG SIM only plans that won’t break the bank.