Sky Mobile 1GB SIM, £1/mo (£5 after 12 months), 24 months
1GBof 5G data
1 GBof 5G data
£1.00a month
£0.00 upfront- No upfront cost
Buy nowat Sky Mobile
at Sky MobileDeal details
Three SIM-only deals
Three SIM-only plans run on the UK's largest 5G network and offer Go Roam passes for Europe and beyond. Live deals coming soon.
List of SIM-only deals (459)
459 deals · from 10 retailers · Updated 1h ago
We list no Three deals on this page, so here are the closest deals
Showing all SIM-only deals from other networks. The network and seller are named on every deal. Three deals appear here when a provider lists them.
24 month contract
£1 a month on a 24-month contract, with price rises each year
Mozillion Pay Monthly Plus 10GB 24 months (£62.50 upfront + £2.50/mo)
10GBof 5G data
10 GBof 5G data
£2.50a month
£62.50 upfront- NEW
Buy nowat Mozillion
at MozillionDeal details
Mozillion Pay Monthly Plus 30GB 24 months (£68.75 upfront + £2.75/mo)
30GBof 5G data
30 GBof 5G data
£2.75a month
£68.75 upfront- NEW
Buy nowat Mozillion
at MozillionDeal details
Mozillion 1GB SIM Only, 12-month
1GBof 5G data
1 GBof 5G data
£2.75a month
£33.00 upfront- NEW
Buy nowat Mozillion
at MozillionDeal details
Lebara 15GB SIM, £2.80/mo for 6 months then £7/mo, rolling monthly…
15GBof 5G data
15 GBof 5G data
£2.80a month
No mid-contract price rise£0.00 upfront- No upfront cost
- 1-month rolling
Buy nowat Lebara
at LebaraDeal details
Mozillion 80GB SIM Only, 24-month
80GBof 5G data
80 GBof 5G data
£3.00a month
£75.00 upfront- NEW
Buy nowat Mozillion
at MozillionDeal details
Lebara 30GB SIM, £3.20/mo for 6 months then £8/mo, rolling monthly…
31GBof 5G data
31 GBof 5G data
£3.20a month
No mid-contract price rise£0.00 upfront- No upfront cost
- 1-month rolling
Buy nowat Lebara
at LebaraDeal details
Mozillion Pay Monthly Plus 100GB 24 months (£81.25 upfront + £3.25/mo)
100GBof 5G data
100 GBof 5G data
£3.25a month
£81.25 upfront- NEW
Buy nowat Mozillion
at MozillionDeal details
Mozillion 3GB SIM Only, 24-month
3GBof 5G data
3 GBof 5G data
£3.50a month
£84.00 upfront- NEW
Buy nowat Mozillion
at MozillionDeal details
Mozillion 210GB SIM Only, 24-month
210GBof 5G data
210 GBof 5G data
£3.50a month
£87.50 upfront- NEW
Buy nowat Mozillion
at MozillionDeal details
Mozillion 3GB SIM Only, 12-month
3GBof 5G data
3 GBof 5G data
£3.75a month
£45.00 upfront- NEW
Buy nowat Mozillion
at MozillionDeal details
Mozillion 260GB SIM Only, 24-month
260GBof 5G data
260 GBof 5G data
£3.75a month
£93.75 upfront- NEW
Buy nowat Mozillion
at MozillionDeal details
Mozillion Pay Monthly Plus 310GB 24 months (£100 upfront + £4/mo)
310GBof 5G data
310 GBof 5G data
£4.00a month
£100.00 upfront- NEW
Buy nowat Mozillion
at MozillionDeal details
Mozillion 30GB PAYG 24 months (£4/mo)
30GBof 5G data
30 GBof 5G data
£4.00a month
£96.00 upfrontBuy nowat Mozillion
at MozillionDeal details
Mozillion 3GB SIM, £4.50/mo, 1-month rolling
3GBof 5G data
3 GBof 5G data
£4.50a month
£4.50 upfront- 1-month rolling
- 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 upfrontNetwork offer: Use LEBARA3M at checkout for 3 months half price
- NEW
Buy nowat Lebara
at LebaraDeal details
Lebara 5GB SIM, £5/mo, 1-month rolling
5GBof 5G data
5 GBof 5G data
£5.00a month
No mid-contract price rise£5.00 upfrontNetwork offer: Use LEBARA3M at checkout for 3 months half price
- 1-month rolling
- NEW
Buy nowat Lebara
at LebaraDeal details
Mozillion 100GB PAYG 24 months (£5/mo)
100GBof 5G data
100 GBof 5G data
£5.00a month
£120.00 upfrontBuy nowat Mozillion
at MozillionDeal details
Sky Mobile 10GB SIM, £5/mo, 24 months
10GBof 5G data
10 GBof 5G data
£5.00a month
£0.00 upfront- No upfront cost
Buy nowat Sky Mobile
at Sky MobileDeal details
Sky Mobile 100MB SIM, £5/mo, 24 months
0.1GBof 5G data
0.1 GBof 5G data
£5.00a month
£0.00 upfront- No upfront cost
Buy nowat Sky Mobile
at Sky MobileDeal details
12 month SIM only contract - Unlimited Minutes & Texts plus 3GB Data
3GBof 5G data
3 GBof 5G data
£5.00a month
£5.00 upfront- NEW
Buy nowat Asda Mobile
at Asda MobileDeal details
24 month SIM only contract - Unlimited Minutes & Texts plus 3GB Data
3GBof 5G data
3 GBof 5G data
£5.00a month
£5.00 upfront- NEW
Buy nowat Asda Mobile
at Asda MobileDeal details
Mozillion 10GB SIM, £5.90/mo, 1-month rolling
10GBof 5G data
10 GBof 5G data
£5.90a month
£5.90 upfront- 1-month rolling
- NEW
Buy nowat Mozillion
at MozillionDeal details
12 month SIM only contract - Unlimited Minutes & Texts plus 10GB Data
10GBof 5G data
10 GBof 5G data
£5.95a month
£5.95 upfront- NEW
Buy nowat Asda Mobile
at Asda MobileDeal details
Showing 24 of 459 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
← Swipe to see all columns →
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. Three switched off its 3G network in November 2025, and its 4G network covers 99% of the UK population outdoors (three.co.uk, as listed on 4 November 2026).
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
← Swipe to see all columns →
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 particularly strong for data-heavy users. The network offers the largest unlimited data range of any UK operator, no speed throttling on unlimited plans, Go Roam passes for 70+ destinations, and competitive pricing. 5G coverage is growing rapidly through the 2025 merger with Vodafone.
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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