SIM-only deals in the UK now start under £10 a month. Vodafone Basics gives 50GB for £8, O2’s online Mini plans start at £7 for 10GB, and SMARTY sells a 16GB one-month plan for £8 with no annual price rise. This guide compares the current deals from all four networks and the budget brands that run on them.
Best UK SIM-Only Deals at a Glance
| Deal | Network | Price | Data | Contract | Good to know |
|---|---|---|---|---|---|
| Mini 10GB | O2 | £7/month | 10GB | 30-day rolling | Online price; EU roaming included |
| Basics 16GB | Vodafone | £7/month | 16GB | 12 months | For customers switching to Vodafone |
| Basics 50GB | Vodafone | £8/month | 50GB | 12 months | Rises to £9.50 on 1 April 2027 |
| 60GB Black Friday deal | O2 | £8/month | 60GB | 12 months | Rises by £2.50 each April |
| 16GB plan | SMARTY (Three network) | £8/month | 16GB, currently doubled to 40GB on offer | 1 month rolling | No credit check, no annual price rises |
| SIM-only range | Three | From £11/month | 4GB to unlimited | 12 months | 30-day plans start at £19/month |
| Unlimited Lite | Three | £22/month | Unlimited | 24 months | Cheapest big-network unlimited on a long plan |
| Essential 30GB | EE | £24/month | 30GB | 24 months | No perks included; widest 5G reach |
| Unlimited Plus | Vodafone | £26/month | Unlimited | 24 months | Speeds capped at 100Mbps |
Every deal above includes unlimited UK calls and texts. Prices checked on the networks’ own shops in November 2026; Black Friday offers run until early December.
O2: Cheapest Big-Network Start, Free EU Roaming
O2’s online shop leads on entry price. The 10GB Mini plan costs £7 a month on a 30-day rolling basis, and the current 12-month Black Friday deal gives 60GB for £8. Unlimited data starts at £19.99 a month on a 24-month plan. O2 is also the only one of the four networks that still includes EU roaming as standard, up to 25GB. The catch is the annual rise: O2 adds a flat £2.50 a month to airtime plans every April, inside the contract as well as after it.
Vodafone: Basics Range Is the Value Play
Vodafone Basics is a separate, simpler range for people switching from another network. The 12-month plans start at £7 for 16GB, with 50GB at £8, 70GB at £9 and 100GB at £12, all with unlimited UK calls and texts and speeds up to 100Mbps. Prices rise by £1.50 each April. On Vodafone’s main range, 120GB costs £21 a month and Unlimited Plus costs £26 a month on 24-month plans.
Three and SMARTY: Flexibility First
Three sells SIM-only on 30-day, 12-month and 24-month terms. Twelve-month plans start from £11 a month, 30-day plans start from £19, and the 24-month Unlimited Lite plan is £22 a month. SMARTY, which runs on Three’s network, keeps things simpler: every plan is one-month rolling with no credit check and no annual price rises. Its 16GB plan is £8 a month, currently with double data (40GB) on offer, and SMARTY refunds £1 for each unused 1GB on its data-discount plans. EU roaming is included up to a 12GB fair-use limit.
EE: You Pay for the Network
EE is the premium option. Its Essential SIM-only plan costs £24 a month for 30GB on a 24-month contract, with no perks bundled, and Smart plans with swappable perks and included roaming run from about £30 to £50. EE’s draw is coverage and speed rather than price: it consistently tops independent UK network tests. If EE signal is what you need but the price stings, EE’s own additional-line SIMs and its broadband-customer offers are cheaper ways in.
Before You Switch
Check the coverage map for your postcode on each network’s site, because the cheapest deal is worthless without signal at home and work. Watch the April price rise on EE, O2, Vodafone and Three contracts; the monthly price printed today is not the price you pay for the whole term. SMARTY and the other no-rise brands avoid that, which is why they often win over 12 months even when the headline price ties.
New to comparing packages? Browse the full mobile packages hub, and if you are moving between countries, our guides to checking your remaining balance and converting a SIM to 4G/5G cover the basics that apply on any network.
FAQs
What is the cheapest SIM-only deal in the UK right now?
Several deals sit at £7 to £8 a month in November 2026: O2’s 10GB Mini at £7 on a 30-day plan, Vodafone Basics 16GB at £7 and 50GB at £8 on 12-month plans, O2’s 60GB Black Friday deal at £8, and SMARTY’s 16GB plan at £8. Vodafone’s 50GB at £8 gives the most data for the money.
Which UK network has the best coverage?
EE is usually rated the widest and fastest in independent UK tests, but coverage is local. A network that is strong in one town can be weak in the next street, so check your home and work postcodes on each network’s coverage checker before you switch.
Do UK SIM-only prices go up during the contract?
On EE, O2, Vodafone and Three, yes. The rises are now fixed amounts printed in the contract: O2 adds £2.50 a month each April, and Vodafone Basics adds £1.50. SMARTY does not apply annual price rises at all, and its plans are one-month rolling, so you can leave whenever you like.
Can I keep my number when I switch SIM-only deals?
Yes. Text PAC to 65075 from your old SIM to get your porting code, then give that code to your new network when you order or activate. The switch normally completes within one working day, and your old plan ends automatically once the number moves.
Last verified: November 2026
