Last updated: Wednesday 7 October 2026 (Europe/London).
Next update: when Mozillion or Lebara change their 12-month prices or allowances.
By: Switch Editorial Team, Switch Squid Ltd
As of 7 October 2026, the best-value 12-month SIM only deal we found is Mozillion’s 150GB plan at £108 for the year, which works out at £9 a month, with unlimited calls and texts, no credit check and no mid-contract price rises. The catch is that you pay the full £108 upfront; if you would rather pay monthly, Lebara’s 30GB 12 Month Plan costs £9 a month on the Vodafone network. Both cost £108 over 12 months, so the choice comes down to how much data you need and how you prefer to pay. SwitchSquid compares the main year-long options below; we may earn a commission if you buy through our links.
Sources: Mozillion — 150GB 12-month plan, Lebara — 30GB 12 Month Plan, Smarty — 16GB plan and Ofcom — rules on mid-contract price rises.
Mozillion 150GB for 12 months — £108 upfront
- Equivalent to £9 a month when we checked on 7 October 2026
- 150GB of data each month with unlimited UK calls and texts
- No credit check and no mid-contract price rises
- Main limitation: the full £108 is paid upfront for the year
What is a 12-month SIM only deal?
A 12-month SIM only deal gives you a SIM card, or an eSIM, with a set monthly allowance of data, minutes and texts for a year, without a phone. It sits between a 30-day rolling plan, which you can leave with a month’s notice, and the 18- or 24-month contracts the big networks tend to push. You keep your current handset and your number, and you know what the next year of mobile will cost.
There are two main ways to buy one. Some providers, such as Mozillion, sell a year of service for a single upfront payment. Others, such as Lebara, charge a lower monthly price in exchange for committing to 12 months; Lebara says its annual plans are around 10% cheaper than its standard monthly prices. Both approaches can save money over a rolling plan, but they suit different budgets.
A year is also a sensible length for a phone you already own. It is long enough to lock in a good price, but short enough that you are not stuck if prices fall, your usage changes, or you upgrade your handset next autumn.
Why a 12-month plan can beat a longer contract
Since 17 January 2025, Ofcom rules mean new mobile and broadband contracts must set out any price rises in pounds and pence at the point of sale, rather than linking them to inflation. That has made long contracts easier to understand, but many 24-month deals still include a rise each April. Both Mozillion and Lebara say they do not raise prices mid-contract on the plans in this guide, so the price you see is the price you pay for the year.
A 12-month term also lines up neatly with other annual decisions. If you are renting, starting university, or expect to change phone next year, a year-long plan means you can review everything at the same point rather than paying an exit charge on a longer deal.
12-month SIM only deals compared (checked 7 October 2026)
Prices are as listed by each provider when we checked. The 12-month cost is the total you would pay over a year; for the rolling plan, it assumes you keep it for 12 months.
| Plan | Data each month | How you pay | Cost over 12 months | Commitment | Main catch |
|---|---|---|---|---|---|
| Lebara 5GB 12 Month Plan | 5GB | £4.50 a month | £54 | 12 months | 1,000 UK minutes and texts, not unlimited |
| Smarty 16GB (30-day plan) | 16GB | £8 a month | £96 | Rolling, leave any month | Price is only fixed month to month |
| Mozillion 150GB for 12 months | 150GB | £108 upfront | £108 | 12 months, paid in advance | Whole year paid on day one |
| Lebara 30GB 12 Month Plan | 30GB | £9 a month | £108 | 12 months | Five times less data than the Mozillion plan for the same total |
| Lebara 50GB 12 Month Plan | 50GB | £13.50 a month | £162 | 12 months | Costs £54 more than the Mozillion 150GB year |
| Lebara 100GB 12 Month Plan | 100GB | £18 a month | £216 | 12 months | Double the 12-month cost of the Mozillion plan |
| Lebara Unlimited 12 Month Plan | Unlimited | £22.50 a month | £270 | 12 months | Only worth it if you regularly use more than 150GB |
The pattern is clear. If you can afford to pay upfront, Mozillion’s 150GB year gives the most data per pound of anything we found. If you would rather spread the cost, Lebara’s monthly 12-month plans are simple and let you use your data in 36 countries, but you pay more per gigabyte. Smarty’s 16GB plan is the cheapest way to keep complete flexibility.
Mozillion 150GB — £108 for 12 months
- Same 12-month total as Lebara 30GB at £9 a month, with five times the data
- EU roaming in 41 countries, hotspot and wifi calling included
- Keep your number with a PAC code
Mozillion 150GB for 12 months: what you get
Mozillion lists the plan at £108 for 12 months, which it describes as equivalent to £9 a month. Each month you get 150GB of data with uncapped 5G speeds, plus unlimited UK calls and texts. The plan includes hotspot use, wifi calling and EU roaming in 41 countries, and you can keep your existing number. Mozillion says there is no credit check and no mid-contract price rise.
The main limitation is the upfront payment. £108 in one go is a bigger outlay than £9 a month, even though the yearly total is the same as Lebara’s 30GB plan. Mozillion also sells eSIMs; its own guidance says most recent iPhone models from the iPhone 11 onwards, Samsung Galaxy S20 to S25 models and Google Pixel phones support eSIM, and you can check yours by dialling *#06# and looking for an EID number.
It particularly suits people who use a lot of mobile data, such as those who stream on the commute, tether a laptop, or do not have reliable home broadband. Our Mozillion 150GB guide covers the 24-month version of the plan as well.
Lebara 12 Month Plans: the pay-monthly option
Lebara runs on the Vodafone network. Its 30GB 12 Month Plan is £9 a month and includes unlimited UK minutes and data use in 36 countries. Lebara describes its annual plans as “no contract” and says they need no credit check, but the price is tied to a 12-month plan, so read Lebara’s terms on ending the plan early before you order. Lebara also sells 30-day plans, and some of its monthly offers can undercut the annual price, so it is worth comparing both on Lebara’s site before committing.
The Lebara ladder is easy to follow: 5GB at £4.50, 30GB at £9, 50GB at £13.50, 100GB at £18 and unlimited data at £22.50 a month. The 5GB plan includes 1,000 UK minutes and texts rather than unlimited, so it suits light users who mainly rely on wifi.
How to choose the right 12-month plan
- Check your usage. Your phone’s settings show how much mobile data you used last month. Add some headroom for holidays and busy months.
- Decide how you want to pay. Upfront usually gives more data for the money; monthly is easier on cash flow.
- Check coverage where you live and work. Use the provider’s coverage checker for your home, work and any regular journeys.
- Check eSIM or physical SIM. If your phone supports eSIM, you can often be up and running the same day.
- Keep your number. Text PAC to 65075 to get your switching code, then give it to your new provider. Our PAC code guide explains the process.
Fit summary
- Good for Mozillion 150GB for 12 months: heavy data users who can pay £108 upfront and want unlimited calls and texts with no credit check and no mid-contract price rise.
- Consider Lebara’s 12 Month Plans instead: anyone who prefers a monthly bill, travels regularly to Lebara’s roaming destinations, or needs less data.
- Consider a rolling plan instead: people who may move abroad, change phone soon, or want to leave at a month’s notice.
Important conditions
- Prices and allowances are as listed by Mozillion, Lebara and Smarty when we checked on 7 October 2026 and may change.
- Mozillion’s 150GB plan is paid upfront for 12 months; confirm £108 for 12 months in the basket before paying.
- Lebara’s annual plans are priced for 12 months; check Lebara’s terms on ending a plan early.
- Coverage varies by area; check each provider’s coverage map for your address.
- Fair use and roaming terms apply; check the destination list before you travel.
- We may earn a commission if you buy through our links.
Final decision card
Use a lot of data and can pay upfront → Mozillion 150GB at £108 for the year is the strongest value we found.
Prefer a monthly bill → Lebara’s 30GB 12 Month Plan at £9 a month costs the same over a year, with less data.
Want to stay flexible → a rolling plan such as Smarty 16GB at £8 a month lets you leave at any time.
Check Mozillion 150GB for your phone
- Check coverage at your home and work address
- Check your phone supports eSIM, or order a physical SIM
- Confirm £108 for 12 months in the basket before paying
FAQ
What is the cheapest 12-month SIM only deal?
The lowest monthly price we found is Lebara’s 5GB 12 Month Plan at £4.50 a month, or £54 for the year. It includes 1,000 UK minutes and texts rather than unlimited. For more data, Mozillion’s 150GB plan at £108 for the year gives the most data for the money.
Is a 12-month SIM cheaper than a rolling SIM?
Often, yes. Lebara says its annual plans are around 10% cheaper than its standard monthly prices, and upfront plans such as Mozillion’s can work out cheaper still per gigabyte. A rolling plan costs more over time but lets you leave with a month’s notice.
Do 12-month SIM only deals need a credit check?
Not always. Mozillion says its 150GB 12-month plan has no credit check, and Lebara says its annual plans need no credit check either. Many 24-month contracts from the big networks do run a credit check.
Can prices rise during a 12-month SIM contract?
Under Ofcom’s rules, any planned rise on a new contract must be shown in pounds and pence before you sign. Mozillion and Lebara both say they do not raise prices mid-contract on the plans covered here. Always check the terms shown at checkout.
Can I keep my number on a 12-month SIM?
Yes. Text PAC to 65075 from your current phone to get your switching code, then give it to your new provider when you order or activate your SIM. Your number usually moves within one working day.
Is it better to pay upfront or monthly for a 12-month SIM?
Paying upfront usually gives you more data for the same money; Mozillion’s 150GB year costs the same £108 as Lebara’s 30GB plan paid monthly. Paying monthly spreads the cost and suits tighter budgets. Choose the option that fits your cash flow without stretching it.
What happens when a 12-month SIM plan ends?
That depends on the provider, so check the renewal terms when you buy. It is worth setting a reminder a few weeks before the end date so you can compare deals again. Prices and allowances often change over a year, and a new plan may give you more for less.
