What is SIM Only?
A SIM Only plan gives you data, calls and texts without a bundled handset. You use your existing unlocked phone. Because there is no device financing, SIM Only plans are almost always significantly cheaper than Pay Monthly deals — typically £10–20/month less for the same data allowance.
Contract lengths
- 30-day rolling: cancel anytime with 30 days notice. Maximum flexibility. Three's 30-day plans are exempt from annual rises.
- 12-month: balance of savings and flexibility. Easy to reassess annually.
- 24-month: lowest monthly cost but committed for 2 full years.
Annual price rises by network (2026)
- O2: Fixed £2.50/month each April
- Three: £1.80–£1.90/month each April — 30-day rolling exempt
- EE: £2.50/month from March 2026
- Vodafone: £2.50/month each April
- Tesco Mobile (Clubcard): No rise — price frozen for contract duration
- Sky Mobile: RPI-linked — 30-day exit right on receiving notice
- Lebara: No annual price rises pledged
- iD Mobile: No CPI/RPI rises on SIM Only
Key checks before purchasing
- Is your phone unlocked? All UK phones sold since December 2021 must be supplied unlocked. Older phones: request unlock free from previous network.
- Coverage at your postcode: checker.ofcom.org.uk checks all networks simultaneously.
- 5G included? Confirm whether 5G is free on your chosen tier.
- EU roaming: If you travel to Europe, confirm whether your specific plan includes it free — or calculate the daily charge cost.
kogywall (kogywall.online) is a fully independent information and guidance website. We hold no affiliation, partnership, endorsement, or commercial relationship with O2, Three, EE, Vodafone, Tesco Mobile, Sky Mobile, Lebara, iD Mobile, or any of their parent companies including Virgin Media O2, VodafoneThree, BT Group, Sky UK (Comcast), Tesco plc, Currys plc, or Lebara Group. We do not sell SIM cards, mobile contracts, or devices. We do not access customer accounts, process payments, manage billing, or provide official technical support of any kind. All plan details, pricing and network features change frequently — always verify current information directly with the relevant network before making any decision. Network names, logos and trademarks are the property of their respective owners and are referenced here solely for the purpose of independent consumer information. kogywall operates under UK consumer information guidelines as an independent third-party guidance service only.