SMARTY is owned by Three, and in SMARTY's own words, "the two companies share the same network". Both now sit inside VodafoneThree, the group formed when Vodafone and Three merged. So a SMARTY SIM and a Three SIM use the same masts. The difference is in how you buy: SMARTY is a stripped-back, no-contract brand, while Three sells longer contracts with rewards, stores and phone support.
How do SMARTY and Three compare at a glance?
The table pulls prices and price rises from our live deal feed, so it matches the deals on our comparison pages today. The roaming, eSIM and exit-fee rows come from each network's own pages.
| Feature |  SMARTY |  Three |
|---|---|---|
| Owned by | VodafoneThree | VodafoneThree |
| Runs on | Three's network, plus Vodafone masts where they're shared | Its own network, plus Vodafone masts where they're shared |
| SIM only from | £6 a month | £6 a month |
| Cheapest unlimited data | £17 a month | £14.50 a month |
| Capped data plans | 16GB to 200GB, plus unlimited | 1GB to 250GB, plus unlimited |
| Contracts in our deals | 30-day | 12 months and 24 months |
| Scheduled price rises | None scheduled on current deals | 27 of 27 deals: up £1.80 to £2.30 a month from April 2027 |
| EU roaming | Included. Up to 12GB a month from your allowance. | £2.75 a day. Included on newer Value and Complete plans; 12GB fair use. |
| eSIM | Yes. Available straight away at sign-up; instant swaps from the dashboard. | Yes. eSIM is the default choice at checkout; plastic is the opt-out. |
| Leaving early | Nothing. Every plan is 30-day rolling. | 30-day: nothing. 12 or 24 months: the charges left, less 3%. |
| Deals | See SMARTY deals | See Three deals |
Live rows show the deals in our feed at the last refresh, not every plan a network sells. EU roaming was checked against each network’s own pages on 28 August 2026, eSIM on 26 August 2026, and ownership and exit terms on 23 September 2026. Vodafone and Three masts are shared only at sites where sharing has been switched on: 10,000 of them by April 2026, according to Vodafone.
Is SMARTY cheaper than Three?
Not always. When we checked on 23 September 2026, Three's cheapest unlimited data plan was £14.50 a month on a 12-month contract, rising to £16.80 in April 2027. That comes to £185.50 over the year. SMARTY's unlimited plan was £17 a month on a rolling plan, or £204 over the same 12 months.
So Three was about £18 cheaper over a year for unlimited data, in exchange for a contract, a credit check and a scheduled rise. At the smaller end the picture flips. SMARTY's cheapest plan in our feed was £6 a month for 18GB, while Three's £6 plan came with 1GB on a 24-month contract.
Compare at the allowance you actually need. Our data allowance guide helps you pick it.
Do you have to sign a contract?
SMARTY doesn't use contracts. Every plan rolls monthly, and SMARTY sums it up as "Cancel or change plans anytime. No contracts, no credit checks and no surprises at the end of the month".
Three sells 30-day, 12-month and 24-month SIM plans. Its longer contracts carry the lower monthly prices, but leaving early costs the charges left on the contract, less 3%. On the £14.50 unlimited plan with six months to go, that's about £84.
If you might move, change jobs or want to switch when a better deal appears, SMARTY's flexibility is worth paying for. If you're settled and want the lower price, Three's contract delivers it.
Can the price go up?
On Three's contracts, yes, by an amount you see before you sign. Every Three deal in our feed carried a scheduled April rise, from £1.80 to £2.30 a month depending on the plan. Contracts signed since 17 January 2025 must show that rise in pounds and pence, as our price rise guide explains.
SMARTY says: "We don't do annual price rises with our rolling one month plans". None of its deals in our feed has a scheduled rise. Because its plans roll monthly, you could leave without a fee if it ever changed that.
Will either run a credit check?
This is one of the clearest splits. Three says: "When you sign up for a Pay Monthly plan, we'll run a credit check". SMARTY says: "Because our SMARTY SIM-only deals are paid up-front on a rolling monthly plan, we do not require you to have a credit check".
If your credit history is limited or you'd rather avoid a search on your file, SMARTY gets you onto the same network without one.
What extras do you get with Three?
Three's main perk is Three+, a free rewards app for pay monthly and pay as you go customers aged 18 and over. It offers partner deals and presale tickets. Three also has shops, and phone support on 333: lines open 8am to 8pm on weekdays and 9am to 6pm at weekends. Live chat runs 8am to 10pm on weekdays and 9am to 8pm at weekends.
SMARTY keeps its extras simple. Group plans take 10% off each plan when you bring 2 to 8 together, and referrals can earn a gift card of up to £20. You can "tether and hot-spot all of your data with no speed caps" in the UK. Help comes through a 24/7 chatbot, human chat from 8am to 8pm, email and a community forum, with no phone line.
Which is better for roaming in Europe?
SMARTY includes EU roaming, letting you use up to 12GB of your allowance with unlimited UK and EU calls and texts. Three charges £2.75 a day on most plans. It includes roaming on its newer Value and Complete plans, with a 12GB fair-use limit.
On a week in France on a standard Three plan, the daily fee adds £19.25, based on the charge Three publishes. On SMARTY, it adds nothing. Our EU roaming guide covers every network's terms.
Is coverage the same on SMARTY and Three?
Yes. Both use Three's masts, and both can also use Vodafone masts at sites where the merged networks have switched on sharing. Vodafone names SMARTY and Three among the brands that benefit, with sharing live at 10,000 sites by April 2026.
Ofcom's January 2026 figures for Three's network show 4G reaching 96.6% of premises indoors and 85.0% indoors in rural areas, with 5G at 75.9% of premises outdoors. Ofcom still reports Vodafone and Three separately. Check your postcode on our mobile coverage map.
How does customer service compare?
Ofcom reports on Three but not SMARTY, which falls below the market-share threshold for its reports. Three recorded 2 complaints per 100,000 customers from January to March 2026, level with the industry average. In Ofcom's 2024 customer service survey, 87% of Three customers were satisfied overall against an 88% average. Only 51% were satisfied with how complaints were handled, against a 61% average.
There's no equivalent Ofcom figure for SMARTY, so we don't compare one. What you can compare is how you get help: Three offers phone, chat and shops, and SMARTY offers chat and a forum.
Why you might choose SMARTY
- You want Three's network without a contract or a credit check.
- You want a fixed price with no scheduled rises.
- You travel in Europe and want roaming included.
- You'd bring several SIMs together for 10% off each.
Why you might choose Three
- You want the lowest price on unlimited data and can commit for a year or more.
- You'd use Three+ rewards and presale tickets.
- You want phone support and shops you can visit.
- You're on one of Three's newer plans that already include EU roaming.
How do you switch between SMARTY and Three?
Your signal won't change, since both use the same network. Text PAC to 65075 from your current phone and the code arrives within a minute. Your new network completes the switch within one working day, under Ofcom's rules. Our switching guide covers each step.
Leaving SMARTY costs nothing. Leaving a Three contract early costs the charges left, less 3%. Our mobile exit fee calculator works out the Three figure for you.
Sources and how we checked
Prices, contract lengths and scheduled rises come from our live deal feed and refresh whenever the site updates. We checked SMARTY's plan pages, Group plans, roaming page and credit check page, and Three's contact page, credit check page and Three+ page, on 23 September 2026. Service figures come from Ofcom's complaints data and Comparing Customer Service report.