If you’re happy with the phone you’ve got, a SIM only deal offers a great value solution – and, provided your handset is not locked to a particular network, you can switch between service providers as often as you like, all without losing your existing number. You also tend to benefit from some great savings compared to normal SIM deals.

Three Mobile

Time to go back to school! Three Mobile offers unlimited data for just £16 per month but – here’s the catch – the offer is available only to students and others, like teachers and academics, with a .ac.uk email address. There’s no difference in price between choosing a 12 or 24 month plan, but even if you’d prefer not to be locked in for so long (hey, a year is a long time when you’re a student) then you can still opt for a SIM only deal with unlimited data for a mere £4 per month extra. That’s £20 per month, in case math isn’t your strength. Just head to the Student Discounts page on the Three site, enter your .ac.uk address and the lower prices will be reflected.

O2

Use a shedload of data each month? Hey – we’re not judging. If you’re a new customer, O2 will give you 15GB of it, plus unlimited minutes and texts, for just £13 each month. Considering the provider, and its impressive reach, this is pretty sweet – we’re not talking some unknown set-up with a service that fizzles out the minute the postcode changes. You’ll be locked in to a 12-month contract and the cost, on the face of it, is £23 per month – but you get £120 cashback when you sign up, so that reduces the cost by £10 each month.

Giffgaff

For just £15 per month, giffgaff will give you 15GB of data and unlimited texts and talk time. If you run out of data, you can start your next plan early – and you’re also covered in the EU and additional selected destinations.

Plusnet

Of course, not everyone is obsessed with checking out their ex’s new girlfriend’s social media posts, or what Ariana Grande is up to. For those who like to use their phone the good old-fashioned way – for talking and texting – Plusnet have a £7 per month SIM only deal which gives you unlimited texts and talk time, with an additional 2.5GB of data for the odd bit of browsing. Contract-wise, you’re committed for 30 days and you can ‘roam like at home’ in 40 non-UK destinations.

Vodafone

Vodafone offers the peace of mind of great speeds and near-universal coverage – and for just £10 per month you can access these benefits on a SIM only plan. You’ll be locked in for 12-months, which is a lot less flexibility than you get with some deals but, on the flip side, you can switch to another Vodafone SIM only plan during that period. You’ll also score 8GB of data and unlimited calls and texts. Worried about running over your allowance? There’s a data cap built in to the plan, so you’ll get an advisory message when you’re getting close to your limit, and then another when you’ve reached it.

ID Mobile

iD mobile has a bunch of appealing SIM only deals to choose from and they all offer roaming in 50 worldwide destinations, the flexibility of 30-day plans, unlimited texts and calls and the guarantee of unused data rolling over to the next month. If you’re on a budget and don’t need much in the way of data, their £6 per month deal will get you a monthly 1GB and set you back around the same amount as a coffee and a sandwich, while data gobblers can shell out £20 monthly and score a whopping 20GB of data. You don’t even need to worry about knowing what size your phone takes when ordering – you’ll get sent a card comprising standard, micro and nano, so you can just make it into the size you need.

Lesser Known

Some of the lesser-known names can be excellent ports of call when it comes to sourcing a good SIM only deal – and their offerings are often angled towards users for whom phones are primarily used for social media updates (and come on, admit it, the odd bit of stalking). Take VOXI, where just £10 per month will score you unlimited minutes and texts, as well as unlimited social data – plus an additional 6GB of 4G for anything else you might need it for. Like the Zara app, right? There’s no contract, so you can cancel any time, and you can take the benefits with your plan with you into Europe – which means that holiday bragging is a cert.