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Unlimited data: the best UK networks for truly unlimited plans

Unlimited data icon

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

We pick through fair usage policies to find mobile providers with the least-restrictive unlimited data SIM only deals and phone contracts. Last updated: 14th June 2022.

In our unlimited data guide

There are loads of unlimited data plans about now

Unlimited data plans

A few years ago, unlimited data almost disappeared off the radar. But network technology improvements have meant the cost of delivering data for mobile providers has come down.

The result is, there are now more networks offering unlimited data plans than ever before. But as ever, there are ins and outs to how the actual plans work, with fair usage and other limits across many.

In this guide, we rank each network’s unlimited data plans. We find any limits and try to answer whether the deals are truly unlimited. We also pick out some key networks for particular requirements.

Useful link: Skip to network ratings

How we rate each network

EE: generally the best network to use unlimited data on

EE Unlimited banner

No speed caps or fair usageRead FAQs

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If you’re after unlimited data, because you want to use a lot of data as you travel around the country, we think EE are a very sensible choice. They offer unlimited data on phone contracts and SIM only:

EE might not win on cheapness but it’s a case of paying more to get more. Their 4G network is the biggest in the country (double check in places you’ll use your phone here). And their 4G speeds are the best too.

Independent network testers Opensignal put EE’s typical 4G downloads at 44 Mbps, almost twice as fast as the nearest rivals, including their cheaper rivals Three and SMARTY.

And as more and more 5G gets rolled out (see EE’s latest locations here), you’ll benefit from speeds between 131.9 Mbps - 158.30 Mbps according to Speedtest and Opensignal.

As long as you use your SIM for personal use (not commercial), there are no speed limits or fair usage caps on EE. So if you want to invest in quality, an EE unlimited data SIM gives the best overall experience in our view.

Useful link: Read our full EE network review

Three: they’re our best pick for out-and-out value

Three Truly Unlimited data

No caps or speed limits in the UKRead their guide

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If you want to join a main network on an unlimited data plan, our best choice for price is Three. They regularly have the best priced unlimited data deals on SIM only. See their current options below:

You can also get unlimited data on Three’s phone contracts. As multiple retailers sell them, have a look at our Three phone deal comparison page here and filter for unlimited data.

You’ll get 5G data in 300+ towns/cities where available with Three (check their latest coverage here) and their 5G is blisteringly fast. Between Opensignal and Speedtest you can expect 5G speeds between 103.9 Mbps - 246.65 Mbps.

Three say their unlimited data is truly unlimited in the UK, with no speed caps or fair usage policies, as long as you're using it for regular personal use. We’d point out there is a 12GB monthly cap while roaming though.

We do think usage over 1000GB a month will trigger Three looking into whether you’re only using your plan for personal use. You can’t use it for commercial purposes. It’s not a limit though.

Useful link: Three’s own guide to unlimited data

SMARTY: Three’s sub-brand is cheap and flexible for SIMs

Unlimited data, no restrictions

The most flexible plan on the marketRead why

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Another provider high up our list for value is SMARTY. They’re owned by Three but run at an arm’s length. They therefore use Three’s network for coverage (check their map here).

The main thing going for SMARTY on unlimited data is flexibility, as well as low price. They have one plan and it’s on a 1-month rolling deal, with no contract. Here’s its current pricing:

It’s also flexible because you’re allowed to put the SIM in mobile broadband dongles, mobile WiFi devices, tablets and anything else that will take a SIM. That’ll help you get the most of the unlimited allowance.

There are no speed caps vs being directly on Three (read our SMARTY vs Three guide here). You'll even get access to Three's famously fast 5G on SMARTY. Cheap prices but coverage can spoil the experience.

Useful link: SMARTY’s latest news on 5G launch

iD Mobile: decent unlimited data on phones and SIMs

iD Mobile unlimited data

No traffic management on unlimited plansSee the policy

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As with most their products, iD Mobile have extremely competitively priced unlimited data on phone contracts and SIM only, although SMARTY normally undercut them on 1-month SIMs on the same Three network.

There’s nothing to say that iD Mobile put any speed limits on their unlimited data and they actively confirm there’s no fair usage policy within the UK. So it’s genuinely unlimited.

iD now offer 5G data too via the Three network, which currently measures in as the fastest, even though we think EE’s 5G is more widespread. Otherwise you’ll use Three’s 4G, which is decent.

Overally, we’d say for phone contracts, iD are probably one of the best unlimited data networks. For SIM only, they’re decent but beatable. As with all Three-based networks, check coverage up front before committing.

Useful link: Our iD Mobile review

VOXI: unlimited 5G data on SIMs and phones

VOXI Endless Data

Endless data for whatever you wantSee all benefits

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As VOXI are owned by Vodafone, joining them gets you full-speed, full-coverage access to the Vodafone network. You can get unlimited data with VOXI (branded Endless) on a phone contract or SIM only plan:

If you time it right, you can get a decent price on VOXI’s unlimited data SIM, especially considering it’s just on a 1-month plan with no contract, commitment or credit check. But longer deals can beat it.

There is an acceptable usage policy on VOXI but it’s less a personal limit on the number of gigabytes you can use, more about usage that disrupts the network for other users (hogging bandwidth in one locale).

We think if you’re genuinely using VOXI for your own personal use, you should never fall foul of this. We’re happy to describe it as a truly unlimited data deal.

Useful link: All VOXI benefits

Vodafone: speed caps on most unlimited data

Vodafone unlimited data plans

3x tiers of unlimited planSee the options

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Vodafone are typically one of the priciest UK networks, with certain plans that cost even more than their regular range but offer extra benefits on top. There are lots of different unlimited plans to choose from, so let’s go through them:

Firstly there are different tiers of unlimited plan that give you different peak speeds. Their cheapest is Unlimited Lite that limits you to 2 Mbps, their Unlimited plan limits you to 10 Mbps and their priciest Unlimited Max plans don’t limit your speeds.

That means on Unlimited Max you’ll get access to Vodafone’s 5G speeds between 73.3 Mbps - 159.40 Mbps according to Speedtest by Ookla and Opensignal. They’re typically one of the slower 5G networks, but they’re still decently fast.

We think the only one really worth taking is their Unlimited Max plan. There’s not much point getting unlimited data if your speeds are too slow to do anything particularly data-intensive. Their Unlimited Lite plan is definitely not worth it in our eyes.

In any case, there are much cheaper networks with unlimited data that don’t restrict your speeds and offer the same network experience as being on Vodafone directly which we think are worth looking at.

Useful link: Our full Vodafone review

Honest Mobile: they’re honest about a fair usage cap

Honest unlimited

Speed cap after 650GBSee current prices

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If you’ve not heard of Honest Mobile, read our review here. They’re a carbon negative network, using Three (and sometimes backed up by O2/EE when their Smart Signal system is in operation).

Honest offer these two unlimited data plans on SIM only:

They’re straight up about the fact there is a fair usage policy on their unlimited data plan. You’ll be able to use 650GB a month, before they’ll restrict your data speeds to 3G-level only.

If you want unlimited, because you’re worried about going over limits, this is fine. There’s still no way you can pay extra for data usage in the UK. It’s just you’ll be slowed down.

We expect the same network experience in terms of speed as being on any other 4G network on Three. You don’t currently get 5G. Although this is around the corner with Honest.

Useful link: Honest Mobile’s network FAQs

O2: it’s hard to get excited about theirs

O2 limitless data

650GB fair usage policyRead terms

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If you’re in the market for unlimited data, you’re more than likely quite an expert user that wants to rip through as many gigabytes as you can each month and have a quality network experience.

There’s nothing wrong with O2 when it comes to 4G coverage (unless you’re really out in the sticks). But their 4G speeds leave a lot to be desired. They’re the slowest in the country, according to Opensignal.

Their 5G is on its way to improving this. Where available, you can get typical download speeds between 110.9 Mbps - 127.97 Mbps according to Opensignal and Speedtest. And so far, the faster technology is available in 190+ locations.

You can O2’s unlimited data on phone contracts (see our comparison here) or SIM only. If you catch it while there’s an offer, O2 unlimited data SIMs can compare quite well on price:

But O2 do actively say they'll look into anyone's usage over 650GB twice within one year to check it's not being used for commercial purposes. It's not a set cap though. You can still use it after that.

Useful link: O2’s guide to their 5G

giffgaff: they do have proper unlimited data

giffgaff Always On SIM-only plan

You can't go over limits with Always OnRead their guide

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For many years, giffgaff only offered what is called Always On data with their phone contracts and SIM only plans. It wasn’t proper unlimited data, because your speeds would be limited after 80GB usage.

It’s still available and is fine if you just want the reassurance of not having any data limits to exceed. But if you know you’re a massive data user, it’s not really for you. Here’s the latest price on SIM only:

But now they do also offer a truly unlimited data plan. It’s more expensive than Always On and it isn’t particularly cheap compared to other networks. But it’s 5G on the O2 network:

From a network experience point of view, no O2-based network is particularly exciting for unlimited data. The 4G coverage is generally good but giffgaff are let down by weak 4G speeds (read our review here).

And there's technically the same "650GB twice in a year" rule as O2, where they'll look into your usage if you exceed that per month. So giffgaff don’t really hit a sweet spot of excellent network, excellent price or unrestrictedness.

Useful link: Get £5 free credit

ASDA Mobile: quite a few speed limits built in

ASDA Our unlimited data bundles speed caps

Speed caps keep your usage downSee unlimited plans

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For a short-term unlimited data SIM only the Vodafone network, ASDA Mobile are worth a look. Their plans tend to compare well against other 1-month SIMs, even if they are beatable on price.

There are three separate unlimited plans on ASDA, each with a different data speed cap. We’d steer clear of the 2 Mbps cap plan though, as that’s barely enough to support video streaming.

The 10 Mbps one could be useable. That’s typically enough for video streaming but you wouldn’t want to use it if you’re someone that wants big downloads, fast. For that, you’d want the 150 Mbps capped unlimited plan.

It’s worth noting there’s no credit check to join ASDA Mobile on an unlimited data plan, because you just buy your minutes, texts and data up front each month. So ASDA are good if you have bad credit or no credit history.

Useful link: See ASDA Mobile’s unlimited data page

Tesco Mobile: the only way to get unlimited data abroad

Unlimited data plans from Tesco Mobile

No fair usage while EU roamingRead their guide

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Tesco Mobile offer unlimited data on long-term, but low-cost SIM only contracts. You can take a 12-month or a 24-month contract, but their 24-month contracts tend to work out as better value.

There are absolutely no speed limits so you’ll get the same 4G speeds of 17.1 Mbps (according to Speedtest) and 5G speeds between 110.9 Mbps - 127.97 Mbps (from Opensignal and Speedtest) as you would on their hosts O2.

If you have a Tesco Clubcard (it’s free to sign up for one) you get immediate access to unique deals called “Clubcard prices”. These change now and again, but sometimes there are some brilliant deals on their unlimited data plans.

And finally, Tesco Mobile let you use your whole UK allowance while you’re abroad. That means they’re the only network that let you use unlimited data while you’re in the EU.

Useful link: Tesco Mobile’s guide to their unlimited data plans

Superdrug: a fairly standard unlimited data plan

Superdrug unlimited means unlimited

Simple unlimited dataSee their benefits

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If you’ve never heard of Superdrug Mobile, they’re a smaller provider on Three’s network. They’re pretty competitive for prices on their unlimited data plans, but they’re a little bit pricier than the other networks on Three.

One unique thing about Superdrug is that the money you spend on your monthly bill will be converted into points that you can possibly use to get money off your shopping in Superdrug stores (see how here).

But one drawback is that they don’t get access to their hosts brilliant 5G network. That means you’ll be stuck on Three’s fairly below average 4G speeds.

Finally it’s worth noting that you pay for your Superdrug Mobile plan up front, meaning there are no credit checks to join them and you can cancel your plan whenever you want.

Useful link: Read Superdrug Mobile’s FAQs section

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