SIM Only Deals: A newbie's guide
SIM only deals are ideal if you're looking for a cheap contract without the phone. Because the handset isn't included, the price of most SIM-only plans are very cheap and affordable. And of course, you don't even need a credit check for a lot of SIM-only plans, but check the small print first.
With SIM-Only you get a mixture of calls, texts and data – but you can tailor them to suit your needs. For example, if you're a heavy data user, then you may even want a data only SIM plan.
The best thing to do is compare all SIM Only deals & tariffs here and go from there.
What should I look for, when buying a SIM-only deal?
The main factors to consider are: Price, Contract Length, and Network. Below we have broken each of these down for you into sections:
Price
The price or cost is of course the amount you pay per month. It depends on the length of the SIM-only plan, but the average monthly price is around £9.00 nowadays. But you get a lot for your money, and if you shop around and do a SIM-Only price comparison, you're bound to save even more.
So if you're on a budget, look at the cheapest SIM deals in the UK here and see how much (or little) you will pay per month; you will probably be surprised how cheap it can be. There are many networks to choose from, and not all of them will be as cheap as others, but we'll come to that later.
Contract Length
The Contract Length is, quite obviously, the length of time that the contract will be "live" for. For example, if it says '12 months' then this means it's a year-long contract. You don't need to stay on after the contract is up; this is when it's best to switch and compare, to find a newer SIM contract that represents better value for money.
Or if you want to stay, make sure you read the smallprint because a lot of the time the price will rise after the initial "offer" period is up.
Network
The Network is important because it depends on where you live; if you are lucky enough to live in a rural place then you will know that connection from different networks can be, well, quite spotty!It definitely is worth taking the time to research the different networks – in particular, make sure to check which ones are owned by the "Big Four". In the UK, the "Big Four" are: O2, EE, Vodafone, Three. You'll find smaller networks like VOXI on this website, but they are called MVNOs, or sub-networks. In other words, these MVNOs are just running on a much larger network.
And an MVNO will have the same drawbacks as the network they run on. So for example if you're thinking of moving to VOXI, you'll want to check for Vodafone reviews as well as VOXI reviews, because this is the network that VOXI are using.
It doesn't matter if you choose a main network or a sub-network; SIM Only Deals are all unique in their owns so it pays to compare the pros and cons of each. This way, you can decide which one fits your requirements.
What are the drawbacks of SIM Only Deals?
The biggest (and perhaps only) disadvantage to SIM-Only, is that you have to buy a phone! And as you're no doubt aware, phones are not getting any cheaper; in fact the newest iPhone models can cost around a thousand quid nowadays. But the good news is, you don't need a really flashy phone to get SIM Only. You can use any phone pretty much, even a basic Nokia from many years ago. The only thing you need to check is the SIM card size (more below).
What size of SIM-card will I get?
Normally with a SIM-only deal you get what's called a multi SIM. It should look a bit like this SIM card here. The good news is that it comes with basically different size SIM cards, so one is sure to fit. If in doubt, the best bet is to take out your existing SIM-card from your phone and see what size it is. It will likely be a Micro SIM or a nano SIM.
What is a SIM Only Deal exactly?
SIM Only Deals are essentially a contract that gives you data, texts and calls – but no handset. You typically already have the handset so are looking for the cheapest contract you can get as you aren't paying a monthly fee for your phone. Essentially all you're paying for is either a 30-day or rolling contract, although some SIM Only contracts are up to 18 months long now. But they still work out pretty cheap!
You can also compare SIM only offers by network:
- Compare EE SIM deals
- Compare Vodafone SIM deals
- Compare Tesco Mobile SIM deals
- Compare Plusnet SIM deals
- Compare Giffgaff SIM deals
- Compare O2 SIM deals
- Compare Sky Mobile deals
- Compare Three SIM deals
- Compare Asda Mobile SIM deals
- Compare Lycamobile SIM deals
- Compare Lebara SIM deals
- Compare BT Mobile SIM deals
- Compare Talkmobile SIM deals
- Compare iD Mobile SIM deals, and
- Compare VOXI SIM deals.
Why choose SIM Only?
Generally speaking, SIM only deals are perfect if you already own the phone. Whether it's something flashy like an iPhone 13 or something cheaper, it doesn't matter: SIM Only works for any phone. You will also receive different size SIM cards with your typical contract, including a Micro SIM, Nano SIM and so on. At least one of these will fit into your handset, so don't worry.
Another great thing about SIM Only is that you can often get unlimited data allowances. Coupled with the short-term flexibility of the typical SIM Only contract (which can be as low as 30 days), there really are several compelling reasons to switch to SIM Only today.
About that data allowance...
In the UK, most Britons use around 3GB to 5GB per month through their smartphone. This is per person, not per household, so make sure that your contract has enough data allowance to get you through. Although it's possible to upgrade to a different contract to allow more data, it's generally best to get it right first time if you can.
Which is the cheapest SIM Only contract today?
As of writing this is from Lebara Mobile and costs £3 per month, it includes 250 minutes and 250 texts, and there is no minimum contract length after 30 days has elapsed. So in other words a year's worth of phone usage for 36 quid. Not bad!
As always, you need to check back often as the deals & contract details change often. Here at SIMOnlyDeals we update the latest plan details every few hours. Your best bet is to do a comparison for all UK SIM Only plans.
Are there credit checks for SIM Only Deals normally?
It depends on the network. When you sign up for a Sim-Only contract, whether it is 30 day rolling or a longer 12 month contract, you may need to pass a credit check.
But thankfully, not all networks and providers need a credit check. That is why we've created a comparison page for bad credit and no credit check SIM plans.
Some companies only do 'soft' credit checks rather than a full one, but this varies from company to company. Be aware that Sim Only credit checks are NOT as stringent as those conducted for regular 12 month phone contracts; they are easier to pass. So even if you have been rejected in the past for a 'full fat' phone contract, such as for a monthly Samsung Galaxy S22, it doesn't mean you will therefore be rejected for a SIM Only contract.
Can I cancel SIM Only at any time?
There is no 'one size fits all' answer here: it really depends on the contract length plus of course the terms of each network.
Previously, most SIM Only contracts were 30 days or 'rolling' contracts. This means that they could have been cancelled after only 30 days has elapsed. While these are still around, they are increasingly rare and arguably poor value when compared to longer SIM Only contract lengths. If you were for example going to opt for a 6 month contract versus 30 days, you will probably save more longer term. Of course, it depends on how you use your phone.
What's the disadvantage of SIM Only?
One of the largest disadvantages of SIM only is that the fact that there's no phone. Meaning that you will need to be paying a separate fee monthly or outright to acquire your handset. Given that the average price of a new mobile phone today is around £439, this represents quite a large cost to you.
Although this is fine if you're using your phone to make international calls, even if you are merely planning to make calls to your home country, then this could cost you a great deal of money over the course of a year or two. Should you use your mobile to shoot pictures and videos and upload them to friends via Whatsapp for example, then this price will probably be more economical, but only if you use your phone overseas.
There's a remedy for this issue however: as there are a range of deals out there that will permit you to carry both a landline and a mobile phone, but using exactly the identical telephone number. This sort of deal is called 'Data Only Deals'. Data Only Deals tend to be better than the SIM Only Deals because you don't have to use the network at all. Instead you may use your phone as normal and then use the information to access the mobile network if you need it. Data Only deals will usually include at least 2GB of use a month. This can be raised up to 50GB depending on the plan. Nowadays it's often the case that they are unlimited data.
How to cancel SIM Only early
The clear advantage of SIM Only is the short contract length.
But if you want to cancel your SIM Only deal early then speak to the network: it is likely that any penalty fee will be much lower than if you were trying to cancel a regular mobile phone monthly deal. Why? Because there is no handset so the networks don't need to recoup a large amount of money with SIM Only. Plus, they will probably want to keep you as a customer!
FAQs about SIM Only
Which mobile phone network is best?
When it comes to SIM only, there is a huge selection nowadays to choose from. The first thing you will want to do is check that you can get coverage in your area; here are a few links for you to check coverage from the major SIM networks.
- Vodafone – Check coverage
- VOXI – Check coverage
- Smarty – Check coverage
- O2 – Check coverage
- Lebara – Check coverage
- Three – Check coverage
- Tesco Mobile – Check coverage
- EE – Check coverage
Note that some SIM Only networks like VOXI are owned by Vodafone and use their network. So, in short, if you can get a decent signal with Vodafone then you will be able to get a decent signal with VOXI as they use the same network. Always make sure to check first before you buy, though.
How long should my contract ideally be?
There is no one size fits all answer here, but generally speaking if you can stretch to a longer contract you will very likely save more money long-term.
If you were to opt for a rolling/no-contract SIM Only deal – for example one that is 30 days long – then you will find that these work out more expensive. But of course that is to be expected; since they are shorter contracts you have the freedom to leave any time, and not be tied down to a fixed contract.
It is often a balancing act: pick the shortest SIM Only contract that you can, but make sure that it's affordable and you won't end up paying more than had you opted for a longer contract.
Can I trust smaller networks?
Although you might have not heard of Lebara or Smarty, there is no reason to be concerned. Make sure to check out all our SIM network reviews here as well - for example, we've written an in-depth review of Smarty here. In most cases these smaller companies are owned by the networks anyway – such as in the case of VOXI who are owned by Vodafone.
And anyway, increasingly, the smaller networks and brands are offering the best value. The reason for that is simple: They need to attract customers and don't have the brand cachet of the huge networks like O2 or Virgin Media.
Will my phone work with SIM Only, is my phone unlocked?
If your mobile phone was purchased from 2016 onwards in the UK then yes, it will be unlocked. We know this because by law it has to be. To check if your phone is unlocked, the easiest solution is to ask to borrow a friend's SIM Card briefly. Remove your own SIM from your handset and slide in your friend's one. If it works and connects to the network then you know it is unlocked.
Which SIM Only Deal is most recommended by others?
This is quite a hard question to answer, because it depends on your needs. Uswitch have tried to answer this question with their awards. We don't have any awards here at SIMOnlyDeals, but here is our best pick of the latest December 2024 SIM offers:
| Best SIM Only networks | Winner | Highly commended |
|---|---|---|
| Network of the Year | giffgaff | Sky Mobile |
| Fastest Mobile Network – Powered by OpenSignal | EE | Vodafone |
| Best SIM-Only Network | giffgaff | Three |
| Best Value SIM-Only | SMARTY | VOXI |
| Best Network for Customer Service | Tesco Mobile | Sky Mobile |
| Best Network for Data | Three | O2 |
| Best Network for Roaming | O2 | Three/Vodafone |
| Most Popular Mobile Network | O2 | Three |
| Best Pay Monthly Network | BT Mobile | Tesco Mobile |
| Best PAYG Network | giffgaff | VOXI |
| Best Value Pay Monthly | Tesco Mobile | BT Mobile |
Do I keep my number when I switch to a SIM Only deal?
Yes! You get to keep your number but you will need what's called a PAC Code. It's pretty easy to get one, and keeping your number nowadays is a lot easier than it used to be.
A contract that includes a new or upgraded phone means you will pay for the full cost of that phone (or more) by the time your contract ends.
SIM Only deals don't include this extra cost. Therefore, if you already own a handset, you can save hundreds of pounds a year by switching to SIM Only. If you use your phone a lot, pay monthly is usually the better option. Pay as you go is ideal for modest phone use – saving you money and giving added flexibility.
What amount of data do I need?
The best answer to this question, is to check your current usage. Most smartphones nowadays will tell you this, though it depends what type of phone you have. Here are some possible ways to find out your data usage:
Once you have this information, you will be able to make an informed decision based on past usage patterns. In other words, if you used on average 5Gb per month then it makes sense to choose a SIM-only plan with around 5-7Gb a month. You don't want to leave yourself short, otherwise you'll have to start paying for bolt-ons or additional data, which can be very costly.
