These are the six best SIM only deals available in the UK

These are the best SIM only deals on the market. Upgrade your plan now and enjoy 5G data in 2021

Vodafone SIM only deals
(Image credit: Vodafone)

These are the best SIM only deals available in the UK today. T3 is constantly monitoring SIM plans from the UK's biggest retailers and  networks, and these SIM plans here offer affordable and flexible SIMO packages that will instantly transform how you use your handset.

These are SIMO plans that cost a fraction of what with-phone SIM plans cost and deliver orders of magnitude greater allowances, too.

Some of these SIM only deals even manage to offer unlimited data, texts and minutes, as well as completely contract free commitments. You get the best price, best allowances and best freedom as there is no contract involved – you can cancel at any time.

Others offer very strong 5G packages with short contracts at the UK's very best and fastest networks. Basically, there's a brilliant SIM only deal for everyone right here – and especially as price start at just £10 per month.

Here are the best SIM only deals available right now:

Three SIM only | Unlimited data, texts and calls | £16 p/m | Contract length: 12 months | Available now at Three
Star Deal

Three SIM only | <a href="https://store.three.co.uk/view/content/mbasket?ID=1683&ty=aff&link_id=lc&link_ref=hawk-custom-tracking&aff_id=3713" data-link-merchant="store.three.co.uk"" target="_blank" rel="nofollow">Unlimited data, texts and calls | £16 p/m | Contract length: 12 months | Available now at Three
Three's 5G ready SIM here delivers unlimited data, minutes and texts for just £16 per month, which is the cheapest unlimited everything plan on the market today. This plan only has a short 12 months contract length, too.

SIM only | 1 month rolling plan | Cancel anytime | Unlimited data, calls and texts | £16 p/m from Smarty

SIM only | 1 month rolling plan | Cancel anytime | Unlimited data, calls and texts | <a href="https://www.awin1.com/awclick.php?awinmid=10933&awinaffid=103504&clickref=hawk-custom-tracking&p=https%3A%2F%2Fsmarty.co.uk%2Fplans%2Funlimited%3Fvc%3D12MthUnlimited16Jan21AFF%26utm_campaign%3Dawin%26utm_medium%3Daffiliates%26utm_source%3DTechRadar%26utm_content%3DEditorial%2BContent%26awc%3D10933_1612261969_330050c58cb7e741de58cab081aa2f84" data-link-merchant="smarty.co.uk"" target="_blank" rel="nofollow">£16 p/m from Smarty
This is simply a remarkable SIM only deal from Smarty, with the supplier delivering unlimited data, texts and calls, along with no contract commitment at all, for just £16 per month. The data on offer is not 5G, though, so if you have a 5G phone or live in a 5G area you're probably better off with the Three plan above.

Vodafone SIM only |&nbsp;100GB data | Unlimited calls and texts | 12-month plan | £16 per month

Vodafone SIM only | <a href="https://www.awin1.com/awclick.php?awinmid=380&awinaffid=103504&clickref=hawk-custom-tracking&p=https%3A%2F%2Fwww.mobiles.co.uk%2Fvodafone-sim-only-deals%3Ffilter_tariff_5g%3Dtrue" data-link-merchant="mobiles.co.uk"" target="_blank" rel="nofollow">100GB data | Unlimited calls and texts | 12-month plan | £16 per month
Here's a very tidy SIM only deal that can be bagged right now over at Mobiles.co.uk. It delivers a SIM plan with a 12-month contract that offers a whopping 100GB of data to burn each month, along with unlimited calls and texts. The monthly fee is a very affordable £16, which is then reduced to just £11.50 with a cashback program.

Smarty SIM only | 1 month rolling plan | 50GB data | Unlimited calls and texts | £15 per month

Smarty SIM only |<a href="https://www.awin1.com/awclick.php?awinmid=10933&awinaffid=103504&clickref=hawk-custom-tracking&p=https%3A%2F%2Fsmarty.co.uk%2Fplans%2F50gb-data" data-link-merchant="awin1.com"" target="_blank" rel="nofollow"> 1 month rolling plan | 50GB data | Unlimited calls and texts | £15 per month
Here's another great contract-free SIM plan from Smarty that delivers freedom to walk away whenever you want. This one delivers 50GB of data and unlimited calls and texts for just £15 per month.

Voxi SIM only | 1 month rolling plan | 12GB data | Unlimited calls and texts | Endless Social Meida | £10 per month

Voxi SIM only | <a href="https://www.awin1.com/awclick.php?awinmid=10951&awinaffid=103504&clickref=hawk-custom-tracking&p=https%3A%2F%2Fwww.voxi.co.uk%2Fplans" data-link-merchant="voxi.co.uk"" target="_blank" rel="nofollow">1 month rolling plan | 12GB data | Unlimited calls and texts | Endless Social Meida | £10 per month
Voxi loves its Endless offers, and this 12GB for £10 per month SIM only deal offers Endless Social Media, meaning you can engage on social media platforms without touching your data allowance, which is 12GB per month. £10 for 12GB is great value.

EE SIM only | 24-month contract | 120GB data | Unlimited calls and texts | £20 per month

EE SIM only | <a href="https://www.awin1.com/awclick.php?awinmid=31423&awinaffid=103504&clickref=hawk-custom-tracking&p=https%3A%2F%2Fshop.ee.co.uk%2Fsim-only%2Fpay-monthly-phones" data-link-merchant="ee.co.uk"" target="_blank" rel="nofollow">24-month contract | 120GB data | Unlimited calls and texts | £20 per month
EE is the UK's fastest mobile network, and its SIM plans come with lighting fast 5G data capabilities unlocked. Right now EE's 5G Essential Plan is only £20 per month, and it delivers a huge 120GB of data each month along with unlimited calls and texts. You also get free EU roaming and 6 months free of Apple Music. This comes on a 24-month contract, however.

To compare these SIM only deals to the rest of the market be sure to take a look at T3's SIMO deals comparison tool below. This not only surfaces the very cheapest SIM only deals, but also lets you filter them by a wide-variety of things, such as contract length, price, data allowance, network coverage, 5G and more.

Robert Jones

Rob has been writing about computing, gaming, mobile, home entertainment technology, toys (specifically Lego and board games), smart home and more for over 15 years. As the editor of PC Gamer, and former Deputy Editor for T3.com, you can find Rob's work in magazines, bookazines and online, as well as on podcasts and videos, too. Outside of his work Rob is passionate about motorbikes, skiing/snowboarding and team sports, with football and cricket his two favourites.