Compare unlimited SIM only deals
Compare the latest unlimited SIM only deals, plans and tariffs from the leading mobile providers. Our comparison includes prices, contracts, data, and much more.
Unlimited SIM only deals explained
In this guide
- Unlimited SIM deals
- Do I need unlimited data?
- Which providers offer unlimited SIMs?
- Best alternatives
- Frequently asked questions
We're near a point now where the amount of data being offered to customers of pay monthly (with a handset) or any sort of SIM only mobile deal is often so high it might as well be unlimited. And when we consider that 75% of the data we exchange to and from our phones is over wifi, we have to ask ourselves: Do we even need limitless data? Maybe.
Maybe your job means you're up and down the country most of the time. Maybe you're a taxi driver and you want to enjoy Netflix during the hours you spend in a queue at the rank. Maybe you just want to watch YouTube on your commute every morning and evening.
But wanting or needing an unlimited SIM deal means your choice of provider and package is going to be severely narrowed, with only a few providers offering them, and some of those on fairly unattractive terms. Let's take a closer look.
What is an unlimited SIM deal?
Technically, an unlimited SIM deal could refer to a SIM, of whose attributes at least one is unlimited. Unlimited calls, for example, or unlimited texts. In reality, though, when we say 'unlimited SIM' what we really mean is unlimited data. The reason we don't call it an unlimited data SIM is because the term 'data SIM' is already taken, and refers to a SIM for your tablet or laptop that doesn't include any calls or texts.
We should count ourselves lucky really. There are plenty of terms out there (broadband only or fibre broadband for example) where consumers mean one thing by them and providers mean another. Unlimited SIMs have unlimited data. Here's some definitions.
- Unlimited minutes – Minutes on calls are unlimited, but only to certain numbers. Generally speaking you can call numbers beginning with 01, 02, 03, 07 and 080. While any number starting with 084 or 087 or 09 is chargeable. Rules do sometimes vary from one provider to another, though, so if you're unsure you should always check
- Unlimited texts – With apps like WhatsApp and Apple Messages, the need for traditional SMS messaging has fallen away in recent years. That said, if it is something you still use, all your SMS messages will be free with unlimited texts. However, your provider will likely still charge you if you send a picture message via SMS, and it's no small amount either, so be aware
- Unlimited data – No limit on the data you use via 4G. On most unlimited data plans there aren't even any limits on how much data you can use by tethering. Up until the latter half of new year, Three (who pioneered all-you-can-eat data in the UK) removed its tethering limit, which had previously been set at 30GB
Is unlimited data really necessary?
Put it this way; you'll know if you need it. With UK mobile users, on average, drawing 75% of their mobile data over wifi, unlimited data is only really useful in a handful of situations.
What we'll do then is take a look at some of the situations you may find yourself in if you do indeed really need an unlimited SIM deal. Hopefully, even if none of them describe you specifically, it'll give you enough of a flavour to decide whether or not unlimited data is for you.
- You're almost never near your wifi – For whatever reason you spend more time outside of the range of your home, work, or indeed any public wifi signal, and you use a lot of mobile data
- Your home broadband is terrible or non-existent – 4G can act as a replacement for slow, inadequate or non-existent home broadband. Particularly remote rural homes often suffer this problem, though not exclusively
- You work on the go – Some jobs mean you're on the road a lot, often only returning home a few times per week. People with these sorts of occupations can chew through a lot of data, especially if they like to entertain themselves with Netflix and whatnot
- Unlimited deal is cheaper than a large-limit deal – Within individual providers, the unlimited option is likely to be the most expensive. However, you will find that the larger data allowances from other providers are sometimes more expensive than unlimited data from those providers who offer it
Which providers offer unlimited SIMs?
Relatively few providers offer unlimited SIM deals, but as time goes on, this number is likely to climb. The introduction of 5G over the next few years will undoubtedly see 4G data limits evaporate across many, if not all providers. For now, though, there are just a few who offer it, and in the case of some there are rules and/or limitations.
- Three – Calls its unlimited SIM deals 'all you can eat'. They're available to all with no restrictions on data usage. You can also opt for an all you can eat SIM if you're getting a Three pay monthly deal that includes a handset
- giffgaff – Offers unlimited everything either with a SIM only or pay monthly handset deal. However, giffgaff will severely restrict your data speeds once you hit 20GB of data each month. Data speeds after you hit this soft limit drop to 384Kbps, which is fast enough for social media and basic web browsing, but too slow for video and other data-intensive uses
- Virgin Mobile – Offers truly unlimited SIMs with no restrictions on data usage on the EE network, and also no slow-downs as in the case of giffgaff. However, you can only get this SIM if you are a Virgin Media broadband and/or TV customer. And since Virgin Media is only available to around 60% of the UK, that means that by default almost half of us can't get this deal even if we wanted to
- SMARTY – Is owned by Three. From the outside, it's pretty hard to fathom why Three needs two brands offering the same sort of stuff. Likely marketing reasons. Anyway, SMARTY offers unlimited everything SIMs on the Three network, and they're a bit cheaper than Three's
Which providers offer good alternatives?
As outlined above, unless you're almost always somewhere where there's no wifi and you pretty much stream video the whole time, you probably don't actually need an unlimited SIM. Chances are you can make do just as well with a SIM with a very high data limit. Here are some alternative providers you might wish to consider, along with which network they're on and the number of gigabytes in their highest data tariff.
- Sky Mobile – Is on the O2 network, but if you're after massive data, Sky Mobile probably isn't the right choice. It offers SIMs in sizes up to 20GB, which if you're someone who's after unlimited data probably won't be enough
- BT Mobile – Is on the EE network and offers SIMs in sizes up to 40GB. That's a lot of data. You could stream video using your mobile data for 1-2 hours every day and not hit that limit. The larger-capacity BT Mobile SIM deals are on the pricey side, though, so be aware
- Virgin Mobile – Is on the EE network, and as outlined above does actually offer truly unlimited SIM deals, but only to its broadband and TV customers. If you're not a Virgin Media customer, you can get SIMs with limits up to 40GB at reasonable prices
- EE – With its own network, EE can afford to be a heavy hitter on data. It offers SIMs with limits up to 60GB, though at this top end you'll be paying more than you will on any of the unlimited SIM deals you'll see in the comparison at the top of this page
- Three – Is on its own network. Outside of its 'all you can eat' unlimited SIMs, which we've already covered in detail, it offers SIMs with data limits up to an incredible 100GB, and at a price cheaper than SIMs from many other providers that offer a fraction of that. Three is the undisputed king when it comes to data
- Plusnet Mobile – Is on the EE network, but if lots of data is what you're after, you should look elsewhere. Plusnet's biggest SIM is a mere 6GB in size
- Tesco Mobile – Is on the O2 network and offers SIMs with up to 50GB of data. That's a lot, and would probably cater to most people who are after an unlimited SIM. However, Tesco Mobile isn't the cheapest when you're looking at its biggest SIMs. Its 50GB offers are considerably more expensive than Three's 100GB or all-you-can-eat SIMs
- Vodafone – Is on its own network and offers SIMs with data limits up to 80GB. While that is one hell of a lot of data, you'll also be paying nearly double what you'd pay for a 100GB limit deal on Three
- O2 – Offers limited SIMs up to 50GB in size. They're not the cheapest, but they're far from the most expensive
- giffgaff – Is on the O2 network. Outside of its unlimited data SIMs (on which it slows down your data speeds to near-unusable speeds when you hit 20GB – giffgaff offers SIMs with limits up to (you guessed it) 20GB. Probably not enough for someone whose data needs see them scouting about for an unlimited SIM deal
- Asda Mobile – Is on the EE network. It only offers pay as you go (PAYG) SIMs, but the amount of data in its 30-day bundles (which you can buy with your top-up) are actually pretty good. 30GB at the top end may well be enough for many, even those with pretty sizeable data requirements. However, being PAYG means you will be paying more than you will on a 12-month contract nine times out of ten
- iD Mobile – Last, and pretty much least, iD Mobile from Carphone Warehouse is on the Three network. Being on Three you'd expect its data limits to be huge, but quite the opposite is true. It's biggest SIM is a mere 12GB, which while plenty for most will almost certainly fall short of the needs of someone in the market for an unlimited data deal
Frequently asked questions
Are there any unlimited data only SIM plans?
Yes. Get reading the guide above, and use our comparison tool at the top of this page.
Do I need unlimited calls and texts as well?
If you're getting unlimited data, you'll find it impossible to find a deal that doesn't also come with unlimited minutes and texts too. Just be aware that your unlimited minutes only apply to numbers beginning with 01, 02, 03, 07 and 080, while any number starting with 084 or 087 or 09 is chargeable. And also that picture messages via SMS (rather than via an app) are chargeable on top of your monthly bill.
Can you get a data only SIM?
Yes. If you have a tablet computer or a laptop with a SIM slot there are plenty of providers willing to offer you a data only SIM with no calls or texts. You can compare data only SIMs on our dedicated page.
Is Virgin Mobile unlimited data really unlimited?
Yes. Data on Virgin Mobile's unlimited SIMs is truly unlimited. However, you have to be a Virgin Media customer to get that particular SIM, and Virgin Media broadband and TV is only available to 60% of UK households. Check if you can get Virgin Media here.
What's the best unlimited mobile plan?
Normally here, we'd offer you a 'how long is a piece of string' answer. But since giffgaff unlimited SIMs come with severe data speed restrictions after 20GB, Virgin Mobile unlimited SIMs aren't available to everyone, and SMARTY unlimited SIMs are just Three unlimited SIMs in a different set of clothes, right now we recommend going with one of Three's all you can eat SIM deals.
Which company has the cheapest unlimited data SIM plan?
It changes all the time. It's usually Three, since you can't really compare giffgaff, which throttles its data speeds once you've used 20GB, Virgin Mobile which not everyone can get and SMARTY is just more Three.
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