Three and iD Mobile are battling it out for the best unlimited data SIM only deal

SIM Only data plans are one of the best ways to get oodles of data without shelling out tens of pounds extra every month because it's tied to a specific handset. If you prefer owning your own smartphone (or tablet or whatever), a SIM Only deal is well worth considering and we've found two incredible ones from Three and iD Mobile.

• Grab unlimited everything from Three for £18/month over 12 months

Not feeling the contract length? iD Mobile has you covered...

• Grab unlimited everything on a rolling one-month plan from iD Mobile for £18/month

The big difference between these two plans, as you may have guessed, is how long the contract is for: Three is offering 12 months of stability while iD Mobile is offering a more flexible month-by-month offering, although contract terms might change.

That's it, that's the big difference. The other fundamentals are identical: unlimited data alongside unlimited texts and calls with great coverage across the UK and abroad for a cheap monthly price.

Three | SIM Only | 12 months | Unlimited data | Unlimited calls and texts | £18/month from Three
On top of the aforementioned data, Three offers a few perks, including 5G readiness at no extra cost, use as a personal hotshot, and roaming around the world. You can rest assured that it has some of the best UK network coverage, too. 

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iD Mobile | SIM Only | 1 month | Unlimited data | Unlimited calls and texts | £20 £18/month from iD Mobile
If you prefer to keep things light and breezy, iD Mobile has you covered: you're never signing up for more than one month of data and you can cancel at anytime, offering extreme flexibility. WiFi Calling is available and bills can be capped at specific limits, too.

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So, if you're looking to take the plunge into the world of SIM Only data plans, or to switch from your existing plan, Three and iD Mobile are both offering incredibly strong deals depending on how long you want to commit to.

• Our guide to the best SIM Only deals
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