Simp comparison
The best unlimited SIM in the UK: an honest, like-for-like comparison
Comparison sites rank on the lowest headline number, and that number is usually one of two things: an introductory price that jumps after a few months, or an “unlimited” plan that's only unlimited for social media while everything else comes out of a capped allowance. When you compare on what you'll actually pay every month for genuinely unlimited data, with roaming included, the picture changes.
Why “cheapest unlimited SIM” lists are misleading
Here's the honest version. Prices checked: June 2026.
Like-for-like: genuinely unlimited data, ongoing monthly price
| Provider | Ongoing price | Genuinely unlimited? | Roaming included | Contract |
|---|---|---|---|---|
| Simp Standard | from £10/mo (£30 quarterly, or £12 monthly) | Yes - data, calls, texts | 10GB EU + unlimited 4G global roaming (3GB at 5G) | No contract |
| Simp Premium | from £13/mo (£39 quarterly, or £15 monthly) | Yes - data, calls, texts | 20GB EU + unlimited 4G global roaming (5GB at 5G) | No contract |
| Lebara | £24.95 | Yes | EU + India | No contract (the £12.50 is intro, first 3 months only) |
| Smarty | £20 (£17 promo) | Yes | EU only | No contract |
| Voxi | £10 advertised | No - unlimited social media only, general data capped (20-60GB) | Paid daily roaming | No contract |
| Three (direct) | ~£14.50 | Yes | Capped roaming allowance | Varies |
| iD Mobile | ~£15 | Yes | EU roaming | Varies |
What this means in plain terms
If you want a plan that's unlimited for everything you do on your phone, and that lets you use your data abroad without paying extra each day, Simp is the strongest value in the UK right now. Simp Standard at £10 a month (paid quarterly) is the cheapest genuinely-unlimited plan on the market, and Simp Premium adds more roaming and rewards from £13 a month.
The plans that look cheaper on a comparison table don't hold up like-for-like:
- Voxi's £10 isn't unlimited data - it's unlimited social apps, with normal browsing, video, maps and downloads coming out of a capped allowance, and roaming charged separately.
- Lebara's £12.50 is an introductory rate for the first three months only. The ongoing price is £24.95 a month - more than two thirds higher than the headline.
- Smarty's unlimited is unlimited but £20 ongoing, and roaming is EU-only, so it doesn't help you outside Europe.
Roaming: the difference is even bigger abroad
Headline price is only half the story. Most UK networks charge a daily fee to roam - even in the EU - and reserve worldwide roaming for their most expensive plans. Simp includes both. Daily roaming charges checked June 2026:
| Network | EU roaming | Worldwide roaming |
|---|---|---|
| Simp | Included | Included - unlimited 4G in 130+ countries, no daily fee |
| Three | £2/day | £5-£8/day (£8/day for new customers from April 2026) |
| EE | £2.59/day | Only on premium Full Works plan |
| Vodafone | £2.57/day | Only on top Xtra tiers |
| O2 | Free in EU (25GB) | £7/day bolt-on or premium tiers only |
| Smarty / Lebara | EU only | Not available |
On a two-week trip outside Europe, that's £28-£112 in daily fees on most networks. On Simp it's included. How Simp roaming works.
Where Simp is different
Simp bundles three things that are rarely found together at this price: genuinely unlimited UK data, calls and texts; global roaming that's actually usable - EU roaming plus unlimited 4G data roaming (with a 5G allowance) in supported countries worldwide, at no daily charge; and no contract with no mid-contract price rises. Both plans are eSIM only, set up in minutes in the app, you can keep your number, and you earn daily rewards on top. They run on the VodafoneThree network.
Like every network, Simp has fair-use limits for normal personal use, and global roaming covers a defined list of countries (in the terms), so it's worth a quick check if you travel somewhere unusual. If you only ever use a little data and never leave the country, a smaller cheap plan may suit you. If you want one plan that's genuinely unlimited at home and works abroad without surprises, that's what Simp is built for.
Simp has 100% 5-star reviews on Trustpilot, with customers regularly highlighting the value, the included roaming and switching from pricier networks like Voxi.
Prices for other networks are sourced from their public pages and major comparison sites and were accurate as of June 2026; they can change, so check the latest before switching.