Mozillion
M
10GBof 5G data
10 GBof 5G data
£2.50a month
£62.50 upfront- NEW
Buy nowat Mozillion
at MozillionDeal details
Three SIM Only Deals UK
Compare every Three SIM only plan: great data, unlimited calls and texts, flexible contracts.
Three SIM Only Deals UK
Compare every Three SIM only plan: great data, unlimited calls and texts, flexible contracts.
List of SIM-only deals (4,899)
4,899 deals · from 5 retailers · Updated 5m ago
We don't have live Three deals right now — here are the closest deals
Showing all SIM-only deals from other networks. The network and seller are named on every deal. We refresh feeds every few hours, so Three deals appear here as soon as they reach us.
24 month contract
£122.50 total cost
Mozillion
M30GBof 5G data
30 GBof 5G data
£2.75a month
£68.75 upfront- NEW
Buy nowat Mozillion
at MozillionDeal details
Mozillion
M100GBof 5G data
100 GBof 5G data
£3.25a month
£81.25 upfront- NEW
Buy nowat Mozillion
at MozillionDeal details
Mozillion
M3GBof 5G data
3 GBof 5G data
£3.50a month
£84.00 upfront- NEW
Buy nowat Mozillion
at MozillionDeal details
Mozillion
M1GBof 5G data
1 GBof 5G data
£3.50a month
£84.00 upfront- NEW
Buy nowat Mozillion
at MozillionDeal details
Mozillion
M1GBof 5G data
1 GBof 5G data
£3.50a month
£3.50 upfront- 1-month rolling
- NEW
Buy nowat Mozillion
at MozillionDeal details
Mozillion
M3GBof 5G data
3 GBof 5G data
£3.75a month
£45.00 upfront- NEW
Buy nowat Mozillion
at MozillionDeal details
Mozillion
M1GBof 5G data
1 GBof 5G data
£3.75a month
£45.00 upfront- NEW
Buy nowat Mozillion
at MozillionDeal details
Mozillion
M3GBof 5G data
3 GBof 5G data
£4.00a month
£96.00 upfront- NEW
Buy nowat Mozillion
at MozillionDeal details
Mozillion
M3GBof 5G data
3 GBof 5G data
£4.00a month
£4.00 upfront- 1-month rolling
- NEW
Buy nowat Mozillion
at MozillionDeal details
Mozillion
M310GBof 5G data
310 GBof 5G data
£4.00a month
£100.00 upfront- NEW
Buy nowat Mozillion
at MozillionDeal details
12 Month Plan
L5GBof 5G data
5 GBof 5G data
£4.50a month
No mid-contract price rise£4.50 upfront- NEW
Buy nowat Lebara
at LebaraDeal details
Sim Only
L5GBof 5G data
5 GBof 5G data
£5.00a month
No mid-contract price rise£5.00 upfront- 1-month rolling
- NEW
Buy nowat Lebara
at LebaraDeal details
Lyca Mobile 30gb
LM30GBof 5G data
30 GBof 5G data
£5.00a month
£5.00 upfront- 1-month rolling
- NEW
Buy nowat Lyca Mobile
at Lyca MobileDeal details
Giffgaff
2GBof 5G data
2 GBof 5G data
£6.00a month
No mid-contract price rise£0.00 upfront- No upfront cost
- No contract
Buy nowat giffgaff
at giffgaffDeal details
Giffgaff
1GBof 5G data
1 GBof 5G data
£6.00a month
No mid-contract price rise£0.00 upfront- No upfront cost
- No contract
Buy nowat giffgaff
at giffgaffDeal details
Giffgaff
25GBof 5G data
25 GBof 5G data
£6.00a month
No mid-contract price rise£0.00 upfront- No upfront cost
- No contract
Buy nowat giffgaff
at giffgaffDeal details
Mozillion
M10GBof 5G data
10 GBof 5G data
£6.00a month
£144.00 upfront- NEW
Buy nowat Mozillion
at MozillionDeal details
5gb
S5GBof 5G data
5 GBof 5G data
£6.00a month
£6.00 upfront- 1-month rolling
- NEW
Buy nowat Smarty
at SmartyDeal details
Id Mobile
25GBof 5G data
25 GBof 5G data
£6.00a month
£0.00 upfront- No upfront cost
- 1-month rolling
Buy nowat iD Mobile
at iD MobileDeal details
Id Mobile
20GBof 5G data
20 GBof 5G data
£6.00a month
£0.00 upfront- No upfront cost
- 1-month rolling
Buy nowat iD Mobile
at iD MobileDeal details
Id Mobile
10GBof 5G data
10 GBof 5G data
£6.00a month
£0.00 upfront- No upfront cost
Buy nowat iD Mobile
at iD MobileDeal details
Id Mobile
8GBof 5G data
8 GBof 5G data
£6.00a month
£0.00 upfront- No upfront cost
Buy nowat iD Mobile
at iD MobileDeal details
18gb
S18GBof 5G data
18 GBof 5G data
£6.00a month
£6.00 upfront- 1-month rolling
- NEW
Buy nowat Smarty
at SmartyDeal details
Showing 24 of 4,899 deals
What Is a Three SIM Only Deal?
A SIM only deal gives you a SIM card with a set amount of data, minutes, and texts each month, but no new phone. Three runs its own 4G and 5G infrastructure across the UK, which means direct control over speed, coverage, and reliability rather than a borrowed signal.
A Three SIM only deal is a great option if:
- You already have a phone you are happy with
- Your current contract has ended and you want to pay less
- You bought a phone outright and just need a plan
- You want more flexibility without being tied to a 24-month handset contract
Three SIM Only Deal Types: Which One Is Right for You?
← Swipe to see all columns →
Why Thousands Choose Three Every Month
1
Award-Winning 5G: Free
5G is included at no extra cost on every eligible Three SIM plan. One of the fastest 5G rollouts in the UK, covering 400+ towns and cities. Just need a 5G-compatible handset.
2
Truly Unlimited Data
Three is one of the few UK networks offering genuinely unlimited data, no speed throttling, no hidden caps. Stream, game, and hotspot without ever watching your usage.
3
Three+ Rewards
Free weekly perks from top UK brands: exclusive discounts, offers, and rewards via the Three+ app. No sign-up fee, no catch. Available on every pay monthly plan.
4
Wi-Fi Calling & eSIM
Make and receive calls over Wi-Fi when mobile signal is weak, great for buildings and rural areas. Most Three plans also support eSIM for instant same-day activation.
Three SIM Only Data Allowances: From 4GB to Truly Unlimited
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Why Three Is the UK's Data Network
Three launched as the UK's first commercial mobile data network in 2003, and data has been the core of what it does ever since. Today, Three's combined 3G and 4G network covers 99% of the UK outdoor population, while its 5G rollout now spans 400+ towns and cities.
Unlike some networks that throttle speeds once you hit a certain threshold, Three's Truly Unlimited plans deliver consistent speeds throughout the month. This makes Three particularly strong for anyone who streams daily, works remotely on mobile data, or regularly uses their phone as a hotspot.
Three also supports Wi-Fi Calling on all eligible plans, making and receiving calls over a Wi-Fi connection when mobile signal is weak. Combined with eSIM support for instant activation, Three has one of the most technically complete SIM-only offerings of any UK network.
More Ways to Get Value from Three
1
Three Student Deals
Three offers student discounts on selected SIM plans, verified through TOTUM (formerly NUS Extra). Can make Truly Unlimited plans significantly more affordable, check before you compare.
2
Pay As You Go SIM
No monthly commitment, no credit check. Three's PAYG data bundles (e.g. 40GB for £20) give far better value than pure credit top-up. Ideal for infrequent users or temporary UK visitors.
3
Data-Only SIM Plans
Three offers data-only SIMs for tablets, laptops, and mobile Wi-Fi routers, same generous data tiers as standard plans, without voice or text. A cost-effective way to keep multiple devices connected.
4
Three+ App Rewards
Every Three pay-monthly customer gets free access to Three+: weekly exclusive discounts from top UK brands, updated every week. No sign-up fee, no catch, available from day one.
How to Switch to Three SIM Only: Keep Your Number
Straightforward, free, and no need to call your old provider
1
Get Your PAC Code
Text PAC to 65075 from your current mobile number, free of charge. Your provider must send your PAC (Porting Authorisation Code) within 1 minute. It is valid for 30 days.
2
Compare Three Deals on Switch
Find the best Three SIM only plan for your data needs and budget. Filter by 5G, eSIM, contract length, or data allowance. Pay monthly plans require a credit check; PAYG plans do not.
3
Activate Your New SIM
Choose physical SIM (delivered in 1 to 2 working days) or eSIM (activated instantly via download). Enter your PAC code during sign-up to keep your existing number.
4
Number Transfers Next Working Day
Three handles the port automatically. You receive a text confirming when the switch is complete. Your old contract ends on the porting date, no separate cancellation call needed.
Three SIM Only vs Other UK Networks
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Using Three Abroad & Credit Check Details
Three's Go Roam scheme lets you use your UK allowance in selected countries worldwide. Go Roam in Europe costs £2 per day across 70+ European destinations. Go Roam Around the World costs £5 per day across 70+ worldwide destinations. Republic of Ireland and Isle of Man are included at no daily charge on most plans.
Note: Three reintroduced EU roaming charges after Brexit. If you travel frequently to Europe, factor the daily Go Roam charge into your overall cost comparison. It can add up on longer trips.
- Pay monthly plans: require a credit check (lighter for 30-day rolling than 24-month)
- Pay As You Go: no credit check at all, available to anyone
- SMARTY and iD Mobile both run on Three's network as MVNOs, often cheaper with fewer extras
- Student discount: verify through TOTUM for additional savings on selected plans
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
Is Three a good network for SIM only?
Yes. Three is one of the UK's four main mobile networks with 99% UK outdoor coverage. It is especially strong on data, offering some of the cheapest unlimited data SIM only deals on the market in 2026, with 5G included free on all eligible plans.
Can I get Three SIM only without a long contract?
Does Three SIM only include 5G?
How much does a Three SIM only deal cost?
Can I keep my number when switching to Three?
Does Three throttle unlimited data?
What networks use Three's infrastructure?
Can I get a Three SIM only deal without a credit check?
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