The fastest SIM deals.
At SIM only prices.
Compare 5G SIM only deals from UK networks. Keep your phone, ditch the overpriced contract, and get 5G speeds for less.
The cheapest 5G SIM only deal we compare is Talkmobile's 80GB plan at £8.95 per month on a 30-day rolling basis, with iD Mobile's 110GB at £10 per month the best value large allowance on a 12-month plan. For unlimited 5G data with no contract, Chattr's Freedom One at £15 per month leads on the O2 network with no mid-contract price rises.
Best 5G SIM only deals right now
Chattr Freedom One (Unlimited)
Talkmobile 80GB
iD Mobile 110GB
giffgaff Unlimited Data
Asda Mobile Unlimited
O2 Unlimited Data (Classic)
VOXI Unlimited
Prices checked August 2026 and may change. Click through to see current offers and confirm availability.
Is 5G actually worth it?
For most people the honest answer is: yes, but the gap is closing. A few years ago 5G SIM plans cost noticeably more than 4G. Now the price difference is small or non-existent, so if you have a 5G phone there is little reason not to be on a 5G plan.
Where 5G makes a real difference is in busy areas. Concerts, stadiums, city centres at peak times, 4G networks get congested and speeds drop. 5G handles the load better. If you commute into a city or spend time in crowded places, the upgrade is worth it.
Do you need a 5G phone?
Yes. Your handset needs to support 5G to connect at 5G speeds. If you put a 5G SIM in a 4G phone, you will still get 4G speeds. Most phones released from 2021 onwards support 5G but it is worth checking your specific model. You can usually find it in your phone settings under network type or on the manufacturer's spec page.
If you are not sure whether your phone supports 5G, check before switching. There is no point paying for 5G access if your handset cannot use it. If your phone is a few years old and does not support 5G, a standard SIM only deal will serve you just as well for less.
Which network should you choose?
Of the providers we compare, Chattr, giffgaff, and O2 direct all use the O2 network, Talkmobile, Asda Mobile, and VOXI run on Vodafone, and iD Mobile runs on Three. All three host networks have strong 5G coverage across UK cities and major towns. The right choice depends on which has better signal at your specific location. Ofcom's free coverage checker is worth using before you commit.
Questions people ask
A 5G SIM only deal gives you a SIM card with access to 5G speeds, without a bundled handset. You use your existing phone. Because there is no device to pay off, 5G SIM only plans are significantly cheaper than 5G phone contracts.
Yes. Your handset needs to support 5G to connect at 5G speeds. If your phone is 4G only, a 5G SIM will still work but you will only get 4G speeds. Most phones released from 2021 onwards support 5G, but check your specific model before switching.
In good signal areas, 5G delivers 100 to 300 Mbps compared to 20 to 60 Mbps on 4G. The difference is most noticeable when downloading large files, streaming high quality video, or in busy crowded areas where 4G networks get congested.
EE has the widest 5G coverage nationally. Vodafone and O2 are close behind with strong urban coverage. Three has competitive 5G speeds in cities. The best network for you depends on your specific location. Check Ofcom's coverage tool before committing.
If you have a 5G phone, almost certainly yes. The price gap between 4G and 5G SIM plans has shrunk to the point where many providers include 5G at no extra cost. If the monthly price is similar, there is no good reason to stay on 4G.
Related deals and guides
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