Cookies on the SIM Sherpa website

We use cookies to track which pages on our website readers visit most. This helps us understand which topics people find interesting, to write more articles about them.

You can accept these tracking cookies or choose to block them. You can change these settings at any time.

X close

✖ Tracking cookies deleted and blocked

Ok, we will not track your page views as you move around any part of the SIM Sherpa website. But we will use that one cookie to remember you don't want to be tracked.

Click here to unblock tracking cookies

X close

✔ Cookies accepted

Thank you for accepting cookies for the SIM Sherpa website. This will help us constantly improve our content.

If you ever want to change your cookie settings for our website, go to our Cookies page here.

Three unlimited data SIM only for £16 a month: order the deal

Three phone and SIM cardVisit

The retailers featured on this page may compensate us when our readers follow links to their websites and make a purchase. More

Get record-low pricing on Three's unlimited everything SIM only plan when you order direct from Three via the hidden link on this page. SIM Sherpa is your trusty guide. Last updated: 21st January 2021.

What's the deal?

Unlimited everything for £16 a month  (4.5/5 deal rating)

Three SIM card

It's unlimited data. And it's priced at just £16 a month - a record-low for Three at any time.

You also get Three's usual benefits of 99% 4G population coverage, inclusive roaming and it comes with 5G data speeds at no extra cost too if your phone supports it.

It's a hidden deal though, it's not advertised on the main part of Three's website. Use this link to go straight to their checkout to buy:

Useful link: Read full benefits below

What's good about it?

It's genuinely unlimited data - and that's pretty rare

Three offer banner

On a 12-month contractSee full offer

(opens in new window)

If you've ever put your phone down because you're worried about going over you data usage limits, Three's unlimited data SIM puts an end to that. You're free to use as much as you like in the UK at no extra cost.

And you're not limited by any sneaky traffic management or throttling rules when you use it in this country either. Others sometimes promise no data caps but then slow you down to stop you using too much.

You can also use it for tethering (personal hotspot), which is where you connect tablets or laptops to your phone so they can access internet anywhere you have mobile signal. That's unlimited in the UK too.

The only restrictions come when you're using your SIM abroad. There, you won't be able to use tethering, a monthly cap of up to 20GB applies (depending where you are) and Three reserve the right to slow down your connection while roaming.

If you managed to use 1000GB in a month, Three say this might trigger them looking into whether you're definitely using the SIM for just personal use (you can't use the SIM for commercial purposes).

That doesn't mean you can't use that much. And it's not an actual fixed limit. It's just the point at which Three might look into your usage.

It's only for your phone though. Don't think you can put it in WiFi routers or dongles and rinse it. Three will detect this and block it.

Useful link: Read Three's terms and conditions

Three's network offers good coverage and speeds

Three's network map

Make sure you'll be able to use unlimited dataCheck Three's coverage

(opens in new window)

It's true that Three aren't the UK's largest network but their 4G now reaches 99% of the population in the places where they live. There is still work to do in rural locations. The deal gets you 5G for no extra cost too.

We'd always recommend checking any network's coverage before you sign up. Use Three's official network map here to do so. Be sure to look not just at home but anywhere you'll be using your phone.

Over 4G, we'd expect Three customers to get download speeds of around 20 Mbps on average, which currently puts them just behind Vodafone and a way off EE.

This is a healthy score that is similar to what many will be getting home over non-fibre broadband. It'll support smooth video and audio streaming and let you browse the general internet.

Customers in these 68 locations also have access to 5G data speeds. Three say it's the UK's fastest 5G network with 140MHz of spectrum, so you can download a high‑res film in seconds.

Useful link: Check Three signal in your area

The £16 monthly cost beats Three's competition

Vodafone's unlimited data plan banner

We do rate Vodafone's Unlimited Max planSee the plan

(opens in new window)

The record-breaking low £16 a month price of Three's unlimited data SIM currently undercuts all other unlimited everything SIMs on the market:

More articles about Three