Three SIM only deals

Our best Three SIMs this week

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 tool.

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.

Read our complete Three network review.

Three’s best unlimited data SIMs

If you’re a heavy data user who doesn’t want to worry about limits, consider Three’s unlimited data SIM deals.

Three has long been known as a data-focused network, and its unlimited plans are designed for streaming, gaming, video calls and hotspot use without constantly checking your allowance. With no data caps, you can browse, download and watch content as much as you like.

Unlimited data SIMs on Three are available across a range of contract lengths, including flexible 30-day rolling options and longer 12-month plans that often come at a lower monthly cost.

Most deals include unlimited UK calls and texts as standard, and many also offer 5G access at no extra cost where coverage is available. This makes Three a strong choice if you want fast speeds and freedom from data limits.

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.

Three’s best rolling contract SIMs

Three’s rolling contract SIMs are perfect if you want flexibility without being tied into a long-term commitment.

These 30-day plans renew each month, so you’re free to change your plan or switch provider whenever you like. They’re ideal if you’re testing a network, waiting for a handset upgrade, or simply prefer the freedom of a short-term deal.

Despite the flexibility, rolling SIM only plans from Three still come with generous data allowances, as well as unlimited UK minutes and texts.

Many plans also include 5G connectivity at no extra cost, letting you take advantage of faster speeds where coverage is available. Because there’s no long contract, these deals offer a convenient and low-risk way to access Three’s network.

Three’s best 12-month SIM deals

If you’re happy to commit for longer, Three’s 12-month SIM only deals can offer excellent value for money. These plans often have lower monthly prices than rolling contracts while still giving you plenty of flexibility compared to longer 18 or 24-month contracts.

Three’s 12-month SIM deals typically include large data allowances, unlimited data, and unlimited UK calls and texts.

Many also come with access to Three’s 5G network where available, helping you enjoy faster downloads and smoother streaming. Choosing a 12-month SIM is a good option if you want a balance between affordability and commitment.

Three’s cheapest SIM only deals

If you’re looking for a low-cost mobile plan, Three offers a range of cheap SIM only deals that keep monthly costs down while still providing reliable connectivity.

These plans are great for light users who mainly use their phone for messaging, occasional browsing and calls rather than heavy streaming or downloads.

Even on the cheapest Three SIM deals, you’ll typically still get unlimited UK calls and texts, along with a modest data allowance to cover everyday use.

Because you’re only paying for the SIM and not a handset, these deals are often much more affordable than traditional phone contracts. They’re an easy way to stay connected while keeping your mobile bill under control.

Read our complete Three network review.

Can I use my Three SIM abroad?

Three no longer includes roaming in Europe on most plans. Instead, you’ll typically need to pay a daily roaming charge to use your UK allowance abroad, often around £2 per day in Europe, with higher charges in other destinations. Known as Go Roam, this usually activates when you use your phone overseas. Always check your specific plan and destination, as charges and allowances can vary.

Can I get 5G enabled Three SIMs?

Yes, Three offers 5G on all its current SIM-only plans at no extra cost. You’ll need a 5G-compatible device and to be in an area with 5G coverage to access it.

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

Yes, you can usually keep your existing number. If you’re switching from another network, you’ll need to request a PAC (porting authorisation code) from your current provider and give it to Three to transfer your number.

If you’re already with Three, you may not need a PAC, but it’s best to check directly with the network.

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

Most modern phones in the UK are sold unlocked, but if your phone is locked to another network, you’ll need to unlock it before using a Three SIM. You can check by trying a SIM from a different provider or contacting your current network.

Are Three SIM only deals cheaper than contracts?

SIM-only deals are often cheaper overall because you’re not paying for a handset. However, phone contracts can spread the cost of a device over time, which may suit some budgets. The best option depends on whether you need a new phone and how you prefer to pay.

What is a PAC code?

A PAC (porting authorisation code) lets you move your phone number from one provider to another. You can request it by text, online or by contacting your current network, then give it to Three to arrange the switch.

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

Yes, you can use your phone as a personal hotspot to share your data with other devices. This will use your data allowance and may affect speeds depending on usage and network conditions.

Does Three offer SIM plans for bad credit?

Three may carry out credit checks for pay monthly plans. If you’re unable to pass a credit check, you may still be able to use Pay As You Go (PAYG) options, which don’t usually require one.