Most people these days get a new phone on contract, but if you can afford to pay for that phone upfront (or you're now out of contract on your phone) it makes much better financial sense to get a SIM-only tariff. In fact, our round-up of the best SIM deals in the UK could save you a fortune in the long run.
A big concern for many is that you'll lose your current phone number if you switch. But that's not true: you can transfer your current phone number to a new network and the whole process is simple if you use the text-to-switch service.
Here, we've picked the very best SIM-only deals available right now. If you're studying at the moment, also check out our article on the best phone contracts for students.
The best SIM-only deals right now
Below we have a more detailed breakdown of the best SIM-only deals; but the best one for this month is a deal from Three - £10 per month for the first six months for unlimited data, calls and texts on a 24 month plan. After the initial six months, the contract goes up to £20 per month. This also includes 5G coverage - take a look at Three's Unlimited SIM here.
There's also a top offer on an unlimited data SIM from Voxi to help those out of work which costs £10 per month (reduced from £35 per month).
Virgin also has introduced two new offers for lockdown - one based for families who are taking on remote learning, and another for vulnerable customers.
The former will grant Virgin mobile customers with families up to 20GB of additional mobile data per month to help with home-schooling. The offer will also a service in which kids can access educational resources without using up any of their mobile data - with Oak National Academy being the first to benefit.
Finally, vulnerable customers who are on Pay As You Go can get a free contract which includes 500 minutes, 500 text messages and 1GB of extra data every month, whilst vulnerable customers on contract can get unlimited minutes and 10GB of additional data every month. These offers will be in place until the end of March.
Visit the Virgin Media website for more information.
Also read: Best SIM deals for kids
Unlike smartphone contracts, which typically stretch to 24 months, SIM-only deals are much shorter. Most SIM-only deals come with 12-month contracts, but there are many rolling monthly contracts – sometimes at the same price – that are ideal for visitors to the UK or for anyone who doesn't want to be tied in.
The price you pay per month will largely depend on how many minutes and texts you need, and how much data you require.
Plus, you'll need to decide whether your SIM is to go in a tablet (in which case you'll only need data) or a smartphone (in which case you'll want minutes, texts and data).
Most operators don't allow you to simply take your SIM out of your smartphone in a tablet. Some often frown upon tethering, so check the Ts & Cs if you want to use your phone's data connection on your tablet, or a second phone.
Pinning down the best SIM-only contract is tricky due to the huge number of combinations of minutes, texts and data available. Some providers also offer deals with cashback redemption - which means that you won't be billed the amount advertised, but you can claim your refunds from the provider.
Most people will fall into one of three camps that we'll focus on here: those who simply want to make the odd call or text, and use their PC to go online; those who make calls and texts, go online, check emails, use apps and perhaps watch the odd video; and those who are permanently glued to their smartphone.
Or, to put that more simply, light, moderate and heavy users.
SIM deals for light use
There are plans available from not much more than £5 per month if you plan on using your SIM for light use.
We'd recommend considering iD, which is Carphone Warehouse's mobile network. All of iD's contracts offer bill capping, data rollover and Roam like at Home making it an even more appealing option with no nasty surprises.
Lebara also offers some great light plans, such as the 2GB rolling plan for £5 per month. With this you also get 100 minutes to 41 international countries - great if you need to call family abroad. You also get 1000 UK minutes and 1000 texts. View Lebara's deal here.
- iD: 5GB data, unlimited minutes, unlimited texts, 4G - £7 per month on a monthly rolling contract. View deal here.
- Vodafone: 5GB data, unlimited minutes, unlimited texts, 4G and free subscription to either Spotify, Amazon Prime or Now TV - £14 per month for 12 months. View deal here.
SIM deals for moderate use
For moderate use, and also for teenagers, the best deal is from Voxi, which is powered by Vodafone.
It's an interesting one, because you get 15GB of data, but social media usage is unlimited and won't eat into that data. That means any Facebook, WhatsApp, Snapchat, Twitter, Instagram, Facebook Messenger, Pinterest and more. Voice and video calls via those apps is not included, but all other activity is.
- VOXI: 15GB data, unlimited social media, unlimited calls and texts, 4G - £15 per month on a monthly rolling contract. View deal here.
You can also get a very cheap deal from ID via Mobiles.co.uk for the same amount of data.
- iD: 20GB data, unlimited calls and texts and 4G - £12 per month for 12 months. View deal here.
SIM deals for heavy use
For anyone who wants the freedom to text and use the internet as much as they like, our favourite deal is Three's long term Unlimited deal for £10 per month for the first six months.
Other recommendations include:
- Superdrug: Unlimited data, unlimited minutes, unlimited texts, 4G, extra card points - £20 per month, one month rolling. View deal here
- Vodafone: Unlimited data, unlimited minutes, unlimited texts, 5G and unlimited download speeds - £14.50 per month for 12 months, save £114 cash by redemption. View deal here.
EE is also offering a bundle SIM deal for iPhone users, called the Full Works SIM. Users get unlimited minutes, unlimited texts and unlimited data, plus the choice of three extras which include Apple Music, Apple TV+, Apple Arcade and BT Sport Ultimate. The SIM-only plans costs £41 per month - but when you factor in the cost of individual subscriptions for each service its quite a decent bundle.
Tablet plans (Data SIMs)
You can't simply take the SIM out of your phone and stick it in your tablet. You need to get a SIM that uses a data-only plan (and don't forget that not all tablets offer SIM-card slots, in which case you'll only be able to connect to WiFi).
How much data you need will very much depend on the activities you intend to enjoy on your tablet, plus whether you spend any of your time within range of a Wi-Fi hotspot. If you want a SIM just to cover you on the odd occasion that you use your tablet away from home and need to continue to access your email, you certainly don't need to pay out extra for a 4G plan.
Some of the best SIM-only deals for tablets come from Three, which offers 2GB for £8 per month, 15GB for £16 per month and 40GB for £18 per month. You can view those deals here.