Keep your phone, get the minutes and data you need, and pay less overall - getting a SIM-only plan certainly has its advantages. If you’re happy with the phone you’ve got, or can afford to buy a new one outright, then you could be much better off going SIM-only.
These plans give you more for your money than pay-as-you-go, but more flexibility than a phone contract - whether you choose a one-month or a 12-month plan.
Take a look at our pick of the best, and choose the right one for you, using our mobile comparison tool - and read on to find out how to get the best deal.
What’s the best SIM deal for me?
The best SIM deal for you will all depend on what kind of phone you have, how much you use it, and what you use it for. To see some of our favourites, check out our guide to the best SIM-only deals right now, otherwise, these might help:
Best SIM-only deal for light use
Not a big mobile user? Pick a cheap SIM plan. If you’re not fussed about getting a big data allowance or lots of calls and texts, go by price instead, and grab the lowest allowance you can get away with.
Of course, some mobile networks may cost a little extra for the same low usage, but come with things that make it worth it - like early bird tickets on O2 Priority.
Best SIM-only deal for heavy use
If you’re a bit more of a phone fiend, go for a plan with lots of data - and look out for unlimited calls and texts while you’re at it. You’ll have to pay a bit more for a big allowance, but if you use it, it’s worth it.
Best SIM-only deal for 4G data
Need lots of 4G data? Take a look at deals with unlimited data allowances. Three has a fab range, and giffgaff offers a kind of unlimited data plan too.
Need the best 4G? Go for a SIM plan from EE - it’s got the fastest 4G speeds and the best coverage of all the UK networks.
Best SIM-only deal for an iPhone 7
Got a brand spanking new iPhone 7 in your hands that needs a SIM to go with it? The best deal for you depends on your use, but to get the most out of this stunner of a phone you’ll want a decent amount of data. To watch a few vids on its HD screen or stream music with your new AirPods, we’d recommend a plan with 5GB data and above.
Oh, and remember you’ll need a nano SIM.
Most flexible SIM-only deal
Grab a 30-day SIM plan, and you can change your allowance (or cancel it entirely) whenever you like. Some networks, like Sky Mobile and Virgin Mobile, let you rollover any unused data to the next month too for even more flexibility.
Best SIM-only deal on a budget
Always choose a large enough allowance for how much you normally use - splashing out for add-ons when you inevitably run out of data will only work out more expensive - but you may be able to get that allowance for a low price from the right network. Take a look at budget providers like iD, giffgaff, and TPO.
Some broadband and TV providers also offer mobile deals, giving you extra savings on their mobile plans if you’re already a customer - perfect when you’re on a budget. These include BT Mobile, Plusnet Mobile, Sky Mobile, and EE. See existing customer SIM deals here.
What allowance do I need?
Monthly allowances on SIM deals can vary hugely, from 500MB and a few hundred minutes all the way up to unlimited everything. So what kind of allowances should you be looking for?
Data
The average smartphone owner uses about 2GB of data per month, so it all depends on how average a user you are.
- If you just use social media, messaging apps, and browse the web on your phone when you’re out and about - 1GB or less is probably fine.
- If you stream music on your phone, watch a bit of video, or browse Facebook and Twitter constantly - Have a look at slightly larger allowances, about 5GB and above depending on your use.
- If you’re a heavy user who streams lots of video on the go, or uses your smartphone for work - Go for a really big allowance. Try 10GB and above, or spring for unlimited data.
Minutes
1000 minutes per month translates to about half an hour of calls per day, while 250 minutes means less than 10 minutes per day. A surprising number of networks offer unlimited minutes, however, which makes life easier.
Texts
Remember that the text allowance on your plan applies just to SMS messages you send - it doesn’t cover anything you send on iMessage, WhatsApp, Facebook Messenger, or other apps (use of these comes out of your data allowance instead).
1000 monthly texts is about 30 per day, so use that as your guide - though, again, a lot of plans have unlimited texts.
Which network should I choose?
SIM-only deals with different networks all come with different benefits. Not only do they each have their own ranges of tariffs, many will also give you a little something extra. With EE, for instance, you get the fastest 4G around, plus a few months of free BT Sport and Apple Music; O2 gives you priority access to tickets for events and shows; and Three offers Feel At Home plans that let you use your allowance abroad.
For all the info you need, see our guide: What’s the best mobile network for me?
But above all, always check you can get good coverage in your area before you commit to a deal with a network.
What kind of SIM card do I need?
This’ll depend on what phone you have. To find out for certain, have a look at the SIM already in your phone, check your phone’s manual, or look up the model’s specs online.
- Nano SIM - The littlest SIM of all. Goes in most modern phones, including iPhone 5 and newer, Samsung Galaxy S6 and newer, HTC One M8 and newer, Motorola X and Z models, and various Blackberries.
- Micro SIM - Smaller than a standard SIM card, but not as tiny as a nano SIM. Goes in iPhone 4s and older, LG G4 and older, Motorola G models, and various HTCs, Huaweis, and other Samsungs.
- Standard SIM - The largest SIM card. Goes in older phones, like the Samsung Galaxy S3 and older, and original Blackberries.
- Combi-SIM - The most convenient SIM. It’s a standard SIM card that contains micro and nano SIMs inside - all you have to do is snap out the size you need and slip that in your phone, whatever the model.
SIM cards for tablets
Got a 4G-enabled tablet? Need a SIM card to put in it so you can use the internet on the go? You’ll need a data-only plan. There’s no point in getting minutes and texts allowances if you can’t use them, after all.
To compare data-only SIM plans - and see our pick of the best - head over to our page here:
Switching networks
Thinking about switching networks to get the best deal? Check out our handy guide to switching our mobile network and keeping your number, and we’ll guide you through the surprisingly simple process.