Mozillion 1GB SIM Only, 12-month
1GBof 5G data
1 GBof 5G data
£2.75a month
£33.00 upfrontEffective £5.50/mo- NEW
Buy nowat Mozillion
at MozillionDeal details
12 Month SIM Only Deals UK
Compare 12 month SIM only deals: fixed price for a year, no two-year lock-in, keep your existing phone.
List of SIM-only deals (80)
80 deals · from 4 retailers · Updated 36m ago
12 month contract
£66.00 total cost
Mozillion 3GB SIM Only, 12-month
3GBof 5G data
3 GBof 5G data
£3.75a month
£45.00 upfrontEffective £7.50/mo- NEW
Buy nowat Mozillion
at MozillionDeal details
Lebara 5GB SIM, £4.50/mo, 12 months
5GBof 5G data
5 GBof 5G data
£4.50a month
No mid-contract price rise£4.50 upfrontEffective £4.88/mo- NEW
Buy nowat Lebara
at LebaraDeal details
iD Mobile SIM Only on 5G 12GB (12 Month contract) with Unlimited mins…
12GBof 5G data
12 GBof 5G data
£6.00a month
£0.00 upfront- No upfront cost
- 5G
Buy nowat iD Mobile
at iD MobileDeal details
Mozillion 10GB SIM, £6.50/mo, 12 months
10GBof 5G data
10 GBof 5G data
£6.50a month
£78.00 upfrontEffective £13.00/mo- NEW
Buy nowat Mozillion
at MozillionDeal details
O2 SIM Only on Classic (12 Month contract) with Unlimited mins & texts…
10GBof 5G data
10 GBof 5G data
£7.00a month
£0.00 upfront- No upfront cost
Buy nowat O2 Mobiles
at O2 MobilesDeal details
iD Mobile SIM Only on 5G 15GB (12 Month contract) with Unlimited mins…
15GBof 5G data
15 GBof 5G data
£7.00a month
£0.00 upfront- No upfront cost
- 5G
Buy nowat iD Mobile
at iD MobileDeal details
iD Mobile SIM Only on 5G 25GB (12 Month contract) with Unlimited mins…
25GBof 5G data
25 GBof 5G data
£7.00a month
£0.00 upfront- No upfront cost
- 5G
Buy nowat iD Mobile
at iD MobileDeal details
iD Mobile SIM Only on 5G 15GB (12 Month contract) with Unlimited mins…
15GBof 5G data
15 GBof 5G data
£7.00a month
£0.00 upfront- No upfront cost
- 5G
Buy nowat iD Mobile
at iD MobileDeal details
iD Mobile SIM Only on 5G 10GB (12 Month contract) with Unlimited mins…
10GBof 5G data
10 GBof 5G data
£7.00a month
£0.00 upfront- No upfront cost
- 5G
Buy nowat iD Mobile
at iD MobileDeal details
iD Mobile SIM Only on 5G 5GB (12 Month contract) with Unlimited mins…
5GBof 5G data
5 GBof 5G data
£7.00a month
£0.00 upfront- No upfront cost
- 5G
Buy nowat iD Mobile
at iD MobileDeal details
iD Mobile SIM Only on 5G 50GB (12 Month contract) with Unlimited mins…
50GBof 5G data
50 GBof 5G data
£8.00a month
£0.00 upfront- No upfront cost
- 5G
Buy nowat iD Mobile
at iD MobileDeal details
iD Mobile SIM Only on 5G 60GB (12 Month contract) with Unlimited mins…
60GBof 5G data
60 GBof 5G data
£8.00a month
£0.00 upfront- No upfront cost
- 5G
Buy nowat iD Mobile
at iD MobileDeal details
O2 SIM Only 60GB Mini (12 Month contract, online exclusive) with…
60GBof 5G data
60 GBof 5G data
£8.00a month
£0.00 upfront- No upfront cost
Buy nowat O2 Mobiles
at O2 MobilesDeal details
iD Mobile SIM Only on 5G 40GB (12 Month contract) with Unlimited mins…
40GBof 5G data
40 GBof 5G data
£8.00a month
£0.00 upfront- No upfront cost
- 5G
Buy nowat iD Mobile
at iD MobileDeal details
iD Mobile SIM Only on 5G 40GB (12 Month contract) with Unlimited mins…
40GBof 5G data
40 GBof 5G data
£8.00a month
£0.00 upfront- No upfront cost
- 5G
Buy nowat iD Mobile
at iD MobileDeal details
iD Mobile SIM Only on 5G 25GB (12 Month contract) with Unlimited mins…
25GBof 5G data
25 GBof 5G data
£8.00a month
£0.00 upfront- No upfront cost
- 5G
Buy nowat iD Mobile
at iD MobileDeal details
iD Mobile SIM Only on 5G 20GB (12 Month contract) with Unlimited mins…
20GBof 5G data
20 GBof 5G data
£8.00a month
£0.00 upfront- No upfront cost
- 5G
Buy nowat iD Mobile
at iD MobileDeal details
iD Mobile SIM Only on 5G 50GB (12 Month contract) with Unlimited mins…
50GBof 5G data
50 GBof 5G data
£8.00a month
£0.00 upfront- No upfront cost
- 5G
Buy nowat iD Mobile
at iD MobileDeal details
iD Mobile SIM Only on 5G 30GB (12 Month contract) with Unlimited mins…
30GBof 5G data
30 GBof 5G data
£8.00a month
£0.00 upfront- No upfront cost
- 5G
Buy nowat iD Mobile
at iD MobileDeal details
iD Mobile SIM Only on 5G 30GB (12 Month contract) with Unlimited mins…
30GBof 5G data
30 GBof 5G data
£8.00a month
£0.00 upfront- No upfront cost
- 5G
Buy nowat iD Mobile
at iD MobileDeal details
Mozillion 30GB SIM, £8.50/mo, 12 months
30GBof 5G data
30 GBof 5G data
£8.50a month
£102.00 upfrontEffective £17.00/mo- NEW
Buy nowat Mozillion
at MozillionDeal details
12 Month Plan 30GB
30GBof 5G data
30 GBof 5G data
£9.00a month
No mid-contract price rise£9.00 upfrontEffective £9.75/mo- NEW
Buy nowat Lebara
at LebaraDeal details
Mozillion 150GB PAYG 12 months (£9/mo)
150GBof 5G data
150 GBof 5G data
£9.00a month
£108.00 upfrontEffective £18.00/mo- NEW
Buy nowat Mozillion
at MozillionDeal details
Showing 24 of 80 deals
What Is a 12 Month SIM Only Deal?
A SIM only deal gives you a SIM card with a set monthly allowance of data, minutes, and texts. Unlike a standard phone contract, no handset is included, so you are not paying off a device. This makes SIM only plans significantly cheaper per month.
A 12 month contract sits between a 30-day rolling SIM (most flexible, slightly higher price) and a 24-month deal (lowest monthly cost, longest commitment). For most people in the UK, a 12-month SIM only plan is the sweet spot: you get a better price than rolling monthly, but you are only locked in for a year.
SIM Only Contract Types: Which Is Right for You?
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Why Choose a 12 Month SIM Only Deal?
There are five strong reasons why a 12-month contract is the most popular SIM only choice in the UK right now.
- Save money straight away: Lower monthly cost than rolling: networks reward commitment with a lower price per month. A 30-day rolling plan with 100GB typically costs £2 to £5 more per month than the equivalent 12-month deal.
- Predictable bills: Price locked for a year: your bill stays the same every month. No mid-contract surprises, no sudden hikes.
- Short enough to stay flexible: You are only tied in for 12 months, not 24. If something better comes out next year, you are free to move.
- Keep your number: Keep your existing number by transferring it with a PAC code. Takes one working day.
- 5G often included: Many networks include 5G at no extra cost on 12-month plans, especially O2, EE, and Vodafone.
Which Networks Offer 12 Month SIM Only Deals UK?
All of the UK's major networks offer 12 month SIM only deals. Here is a quick overview of what each brings to the table.
O2 is one of the UK's biggest networks and offers a wide range of 12-month SIM only plans, from budget data tiers up to unlimited. O2 Priority is a standout perk: subscribers get early access to concert and event tickets, plus regular freebies and discounts. O2's network covers over 99% of the UK population, and 5G is included on most plans at no extra cost.
EE consistently tops coverage rankings as the UK's widest 5G network. Its 12-month SIM only plans include extras like Apple Music or BritBox on selected tiers. If you live outside a major city or travel to rural areas, EE's coverage reach is hard to beat.
Vodafone's 12-month plans are competitively priced and often include international roaming benefits, useful if you travel in Europe. The Vodafone Flexi-Upgrade option lets you move to a different plan before your contract ends, adding flexibility.
Three built its reputation on generous data allowances. Its 12-month SIM only deals are among the most data-heavy for the price, and Three includes roaming in over 70 countries at no extra cost. Go Binge lets you stream from selected apps without it counting towards your data.
More Networks Worth Comparing
1
Sky Mobile
Sky Mobile's standout feature is data rollover: any data you do not use this month rolls into a 3-year data bank you can draw on later. Sky runs on O2's network, so coverage is solid.
2
iD Mobile
iD Mobile (running on Three's network) is one of the cheapest 12 month SIM only deals in the UK for heavy data users. Plans often include data rollover and flexible contract options.
3
VOXI by Vodafone
VOXI is aimed at younger users and is popular for social media and video streaming. Endless social media data means apps like TikTok, Instagram, WhatsApp, and Snapchat do not count towards your allowance.
4
Tesco Mobile
Tesco Mobile runs on O2's network and is one of the consistently cheapest mainstream options for 12-month SIM only deals. Tesco Clubcard members can get additional discounts on their plan.
How Much Do 12 Month SIM Only Deals Cost in the UK?
Prices vary by data allowance, network, and whether 5G is included. Here is a realistic guide to current market pricing for 12 month SIM only deals in the UK in 2026.
← Swipe to see all columns →
Prices are indicative for May 2026. The live deals on Switch are updated daily, so always check for the latest price before you decide.
How to Find the Best 12 Month SIM Only Deal for You
Follow these four steps before you compare.
1
Check Your Actual Data Usage
On iPhone, go to Settings > Mobile Data and look at your monthly usage. On Android, go to Settings > Network > Data Usage. Look at the last 3 months, not just one month, to get your typical figure. Round up by 10 to 20% so you do not exceed your allowance regularly.
2
Check Network Coverage at Your Key Locations
The cheapest deal is useless if the network has poor signal at your home, workplace, or commute route. Use the Ofcom coverage checker at checker.ofcom.org.uk to see which networks have 4G and 5G coverage at your specific locations.
3
Decide Whether You Need 5G
If you have a 5G-compatible phone and live in a covered area, a 5G SIM plan lets you stream, download, and browse at noticeably faster speeds. Most 12-month plans from EE, O2, Vodafone, and Three include 5G at no extra charge on the mid and upper tiers.
4
Compare on Switch and Filter by Contract Length
Go to Switch, set your data amount and contract length to 12 months, and compare every live deal in one place. You can sort by price, network, or extras. Every deal shows the full monthly cost: no hidden cashback conditions or short-term intro prices.
What to Watch Out for With 12 Month SIM Only Deals
A few things are worth checking before you sign up.
How to Switch and Keep Your Number on a 12 Month SIM Only Deal
Keeping your number when you move to a new SIM is simple and free. Here is exactly how it works.
1
Text PAC to 65075 (free)
You will receive your PAC code by text within 1 working day.
2
Compare 12 Month SIM Only Deals on Switch
Pick your plan and start the sign-up.
3
Enter Your PAC Code During Sign-Up
Your new provider handles the number transfer automatically.
4
Your Number Transfers Within 1 Working Day
You will receive a text confirming when the transfer is complete.
5
Insert Your New SIM and You Are Done
Your old number now works on your new network and plan.
You do not need to contact your old network first. The PAC code process is all that is required.
Compare 12 Month SIM Only Deals Now: Free, No Commitment
Switch compares every live 12 month SIM only deal in the UK from all major networks and MVNOs. No sign-up required to compare. No adverts. No hidden ranking by commission. Just the best 12 month SIM only deals sorted by price for your data amount.
Check your data usage, choose your data tier, and compare now. It takes under 2 minutes.
Free AI deals helper
Meet Squid AI, your free deals agent
Say how much data you use and Squid AI picks the cheapest SIM that fits.
No sign-up · answers in seconds
- Save moneyKeep your phone and stop overpaying for data.
- Save timeAnswers in seconds, no forms or sign-up.
- Cheapest SIMSearches live SIM-only prices on every network.
FAQs
What is a 12 month SIM only deal?
A 12 month SIM only deal is a mobile contract that gives you a set amount of data, calls, and texts for a fixed monthly price over 12 months. No handset is included: you use your own phone. At the end of the 12 months, you are free to switch to a new deal or network.
Are 12 month SIM only deals cheaper than 30-day rolling SIMs?
Can I keep my phone number when switching to a 12 month SIM?
Do 12 month SIM deals include 5G?
What happens when my 12 month SIM contract ends?
Can I switch SIM only deals if I am still in contract?
Which network has the best 12 month SIM only deals in the UK?
Do I need a credit check for a 12 month SIM only deal?
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