Unlimited data SIM only deals

You'll find deals from Giffgaff and Chattr on the O2 network, iD Mobile on Three, and Talkmobile on Vodafone, among others. Giffgaff is currently the cheapest at £14 a month, with iD Mobile and Chattr at £15 and Talkmobile at £16. Most of these are MVNOs, networks that rent capacity on a major operator's masts and pass the saving on, so you get the same coverage for less. It is worth filtering by your preferred network or coverage before you decide.

Probably not, and it is worth saying plainly. The average UK user gets through far less data than an unlimited plan offers, so a large capped plan often costs less for the same real world experience. Unlimited earns its place if you tether a laptop regularly, stream in high quality every day, or simply never want to think about running out. Our unlimited data guide goes deeper on fair usage policies, tethering and how each network handles heavy use.

Not always. Several unlimited options, including Giffgaff, Chattr and Talkmobile, can be taken out with no credit check, which helps if you would rather not have a search on your file. Some longer fixed-term contracts do involve a credit check because you are committing for the full term. If a clean credit record is the priority, see our no credit check SIM only deals.

Giffgaff at £14 a month is the cheapest, running on O2 with free EU roaming and no credit check, so it is the pick if price is all that matters and you are happy with an 18 month contract. For most people we would point to iD Mobile at £15 a month instead: it runs on Three with free EU roaming, has no fair usage cap, comes as a SIM or eSIM, and is available on one month, 12 month and 24 month terms, so you can stay flexible or lock the price in. If you want a one month rolling plan with no credit check, Chattr at £15 a month on O2 is also worth a look.

Some deals are advertised with an introductory rate or cashback that changes the real cost. iD Mobile currently has an exclusive 12 month deal at £15 a month with the first three months at £3.75, and other iD Mobile contracts come with automatic cashback. Always check the standard ongoing price and the total cost over the full contract, not just the headline figure. Note too that Giffgaff's £14 price is on an 18 month term, which is longer than the usual one, 12 or 24 month options.

Yes. The unlimited deals listed carry a 5G badge, so you get 5G access at no extra cost where your handset and location support it. Real world speeds still depend on your network's coverage in your area, so it is worth checking the network coverage guide before you commit, especially if you are switching host network.

Yes, though the way it works varies by network. iD Mobile, Chattr and Talkmobile offer their unlimited plans as a SIM or an eSIM from the start, while Giffgaff lets you switch to an eSIM after activating a physical SIM first. If you are not sure whether your handset is eSIM compatible, our eSIM guide explains how to check, or you can browse eSIM only deals directly.

By default, deals are sorted by lowest monthly price. You can change the sort order at any time using the controls above the listings and filter by data allowance, contract length, minutes, and eSIM availability. All deals shown are updated automatically. SIM Only Finder is an Ofcom-accredited UK mobile comparison site and earns a commission on deals taken out via our links. This does not affect how deals are ranked.