Choose your deal
Select your ideal Smarty plan from trusted retailers. Filter by data, price and contract length to find your perfect match.
Compare the latest Smarty SIM-only plans by data, price and contract length, and plant trees with every switch.
Check coverage before you switch
Coverage depends on the network this SIM runs on. Check the signal where you live before you switch.
Smarty is a SIM-only network that runs on Three's network, so coverage and 5G match Three where you are. Every plan is 30-day rolling with no annual contract and no credit check, and some plans refund or discount you for unused data. Plans start from £6.00 a month. Compare the live Smarty deals below.
Quick facts
Smarty uses Three's network for everything, so your signal for calls, texts and data is the same as Three in your area. You get 5G where Three has it. Coverage is the first thing to sort out before any switch, so confirm Three has reliable signal at the places you spend most of your time.
Smarty keeps it deliberately simple: every plan is 30-day rolling, with no annual contract anywhere in the range. You pay month to month and can change or cancel whenever you like, which suits people who do not want to be tied in. Unlimited data plans are available if you are a heavier user. The live deals above show the current allowances and prices so you can pick the one that matches how you use your phone.
The headline draw is the pricing model: low, straightforward costs with no long commitment and no credit check to get started. On some plans you are refunded or discounted for data you do not use, so you only really pay for what you need. With unlimited options at the top end and rolling terms throughout, Smarty is built around value and keeping things uncomplicated.
Smarty suits anyone who wants Three coverage on a tight budget and likes the freedom of paying month to month. Because there is no annual contract and no credit check, it is an easy option if you would rather not be locked in or want to avoid a credit search. The unused-data refund on some plans also appeals to light users who hate paying for allowance they never touch.
Smarty, iD Mobile and Three all sit on Three's network, so coverage is broadly the same. The difference is in how they are sold. Smarty is rolling-only with simple low pricing and an unused-data refund on some plans, iD Mobile adds data rollover and capped contracts, and Three is the network direct with its own rewards. Compare them on monthly cost and the terms that suit you.
Pros
Cons
Our verdict
Smarty is a great fit if you want Three coverage at a low price with no contract or credit check, and the unused-data refund on some plans is a neat bonus for lighter users.
Select your ideal Smarty plan from trusted retailers. Filter by data, price and contract length to find your perfect match.
Keep your current number by texting 'PAC' to 65075. It's free and takes minutes.
Finish your application with Smarty. Your new SIM will be delivered and your number transferred automatically.
Every successful switch through Switchity plants 2 trees through our verified reforestation partner, Ecologi. Our switchers have already captured over 5,240 kg of CO₂ and released nearly 26,986 kg of oxygen annually.
Pick your Smarty SIM-only plan from the comparison above, or browse every UK network we cover.
See all SIM-only dealsEvery switch through Switchity supports reforestation and saves our community money on their broadband.