Last updated: Sunday 1 November 2026
By: Switch Editorial Team, Switch Squid Ltd
On 28 October 2026, Mozillion’s 30GB plan was £7.90 a month on a 1-month plan on EE’s network, so you can leave at the end of any month. You need a 5G phone and 5G coverage to get 5G speeds; on a 4G phone the plan still works at 4G speeds.
Mozillion 30GB for £7.90 a month, 1-month plan
- 30GB with unlimited UK calls and texts for £7.90 a month on a 1-month plan, £94.80 over 12 months, as listed on 1 November 2026
- Runs on EE’s network; 5G speeds need a 5G phone and EE 5G coverage
- Main limitation: confirm 30GB and £7.90 on Mozillion’s page before you pay
On 27 October 2026, the best-value 5G SIM only deals in the UK were mid-data plans: Smarty 40GB at £7 a month with our deal button, or 32GB for £8 on Smarty’s own site, both on 1-month plans (Three); iD Mobile’s 15GB at £6 a month on a 1-month plan (Three), or its 50GB at £8 a month on a 12-month plan as listed on 28 October 2026; and giffgaff’s 40GB at £8 a month on an 18-month plan (O2), with 25GB at £10 a month on the same term, as listed on 1 November 2026; giffgaff says the 40GB for £8 plan is for sign-ups before 4 December 2026. This guide ranks everyday 5G-capable SIMs for shoppers who care about coverage and data-per-pound, not another Unlimited beauty contest. We may earn a commission if you buy using the deal buttons on this page.
Sources: Smarty and iD Mobile plan pages, and giffgaff’s offer announcement of 23 October 2026, checked on 27 October 2026; giffgaff’s plan pages were checked on 1 November 2026.
Offer facts (checked 27 and 28 October 2026)
Plan | Term | Promo price | Data | Network / 5G note |
|---|---|---|---|---|
Smarty 32GB (16GB plan with extra data) | 1-month | £8/mo | 32GB | Three — 5G where Three 5G and your handset allow |
iD Mobile 15GB | 1-month | £6/mo | 15GB 5G | Three — cheapest monthly price here |
iD Mobile 50GB | 12-month contract | £8/mo | 50GB 5G | Three — the most data for £8 here |
giffgaff 40GB | 18-month contract | £8/mo | 40GB | O2 radio — giffgaff says sign up before 4 December 2026; early-exit charges if you leave early |
Smarty Unlimited | 30-day | £20/mo | Unlimited UK data | Only if you truly use more than about 60GB |
“5G” on a plan label means you can use 5G where the host network has built it and your phone supports it. It is not a promise of Unlimited speed in every postcode. Run each retailer’s coverage checker for home, commute and workplace.
What “5G SIM only” should mean in October
Most people typing that phrase need maps, social video and moderate hotspotting on a phone that already speaks 5G — roughly 20–40GB — not a blank data cheque. Paying £20 or more for Unlimited “for the 5G badge” is fine when Settings already shows 60GB+ months; it is expensive habit when you average 18GB on café Wi-Fi.
Illustrative 12-month cost (prices as listed on 27 and 28 October 2026, not quotes):
Smarty 32GB £8 × 12 = £96 (or Smarty 40GB at £7 with our deal button: £84)
iD Mobile 15GB £6 × 12 = £72 (1-month plan, Three network)
giffgaff 40GB £8 × 12 = £96 during the 18-month term (£144 over 18 months)
iD Mobile 50GB £8 × 12 = £96 (12-month plan, Three network)
When Smarty 40GB £7 wins for 5G shoppers
Choose Smarty when Three coverage (including 5G where claimed) is solid, you want an easy exit, and 40GB matches real usage. At £7 a month with our deal button it undercuts many 18-month mid-data contracts on monthly price while keeping the cancellation door open for students, renters and anyone testing a new city signal.
Smarty 40GB SIM — £7 a month with our deal button, 1-month rolling
- 40GB + unlimited UK calls/texts on Three, as listed on 1 November 2026
- Month-to-month, so you can change plan or leave whenever you like
- Confirm 40GB and £7 on SMARTY’s page before you pay
When giffgaff 5G plans fit better
iD Mobile 15GB £6: light users with good Three signal who want a 1-month plan.
giffgaff 40GB £8 / 18 months: stable O2 coverage and you will keep the line for the term.
Skip Unlimited for this brief unless Settings already proves you need it — then read our rolling-vs-18-month and giffgaff-vs-Smarty Unlimited guides instead.
Fit summary
Good for Smarty 40GB £7 with our deal button: Three coverage, mid-data habits, want month-to-month flexibility on a 5G handset.
Good for iD Mobile 50GB £8: Three 5G coverage, want more data for £8 and happy to commit for 12 months.
Good for iD Mobile 15GB £6: lighter data, Three coverage, want the lowest monthly cost on a 1-month plan.
Good for giffgaff 40GB £8: O2 homes willing to commit 18 months.
Not for: heavy hotspotters who routinely pass 60GB — budget for Unlimited instead.
Important conditions
Prices can change, so confirm the retailer page on the day you order, including the data allowance shown.
5G availability is mast- and handset-specific; indoor 5G can drop to 4G.
18-month plans carry early-termination charges.
Fair-use, roaming caps and tethering rules sit in each retailer’s terms.
eSIM vs physical SIM: order early if you are travelling or changing handset the same week.
Keep a PAC text (65075) ready if you are porting your number.
Switching steps
1) Check monthly data use in Settings for the last three months.
2) Confirm your handset is unlocked and 5G-capable if that matters to you.
3) Run Three (Smarty) and O2 (giffgaff) coverage for home and commute.
4) If 40GB and Three look right, order Smarty 40GB at £7 with our deal button.
5) Activate, confirm data with Wi-Fi off, then port your number if needed.
6) Diary any price change dates so a step-up does not surprise you.
Final decision card
Three coverage + mid-data 5G phone → Smarty 40GB £7 with our deal button.
Three 5G coverage + happy with 12 months → iD Mobile 50GB £8.
Light data + lowest price → iD Mobile 15GB £6 (1-month plan).
O2 coverage + stable 40GB need + can commit → giffgaff 40GB £8 / 18 months.
Heavy data → leave the mid-data aisle.
iD Mobile 50GB 5G for £8 a month, 12-month plan
- 50GB of 5G data with unlimited UK calls and texts for £8 a month on a 12-month plan, £96 over the year, as listed on 1 November 2026
- Runs on Three’s network, so check Three 5G coverage for your home and commute
- Main limitation: you commit for 12 months. Confirm 50GB and £8 on iD Mobile’s page before you pay
5G myths that waste money
Myth 1: “I need Unlimited to use 5G.” False. 5G is a radio technology; your allowance still counts megabytes.
Myth 2: “5G always means faster downloads at home.” Indoor walls and mast load matter more than the logo.
Myth 3: “Any 5G phone automatically gets 5G on every MVNO.” The plan and host network must allow it, and the phone’s bands must match.
Worked examples
Renter on a 12-month tenancy: Smarty 40GB at £7 with our deal button keeps an exit door if you move to a Three-weak postcode later.
Parent buying a teen line: a £6 plan such as iD Mobile’s 15GB often covers school Wi-Fi habits; upsize only if gaming hotspotting appears in the bill.
Commuter who maps offline areas: 40GB is the safer mid-data bucket; Unlimited only if tethered laptop days are routine.
Related SwitchSquid SIM guides
For plans under £10 a month, see our under-£10 guide. For Unlimited plans, compare rolling and 18-month terms, or giffgaff and Smarty Unlimited. For several lines in one household, see our family SIM sharing guide. This guide sticks to 5G-ready mid-data deals.
Roaming and EU trips on a £6–£8 plan
UK mid-data plans are priced for domestic use. Roaming allowances are smaller than marketing memory suggests. For a two-week holiday, a temporary travel eSIM can be cheaper than upsizing to Unlimited at home “just in case”.
How to size 15GB versus 40GB without guessing
Open your phone’s data usage screen and look at the last full billing month, not a quiet week on holiday Wi-Fi. Add a buffer of about 20% if you expect a new commute. If three recent months average 10–13GB, a £6 plan such as iD Mobile’s 15GB is usually enough. If you sit at 28–35GB, giffgaff’s 40GB at £8 (18 months) gives more headroom; Smarty 32GB at £8 suits steady users below about 30GB.
Hotspotting is the silent budget killer. A single evening of tethering a laptop for updates can burn 5–10GB. If that is weekly behaviour, stop pretending mid-data will hold.
Handset compatibility still matters. A network-locked phone will not thank you for a perfect £8 plan. Unlock first. eSIM-capable phones can activate faster.
Credit checks, top-ups and bill-payer hygiene
Month-to-month value SIMs are often lighter on credit checks than 24-month handset contracts, but checkout prompts vary. Top-up brands need a funding method you will actually remember. Parents paying for a teen line should decide whether the account sits under the teen’s login or a parent email. Diary the first renewal so a promo step-up does not become a surprise Direct Debit.
If you port a number, activate the new SIM first, confirm data with Wi-Fi off, then send the PAC. Porting into a dead SIM is how people lose a day of service on a Monday morning commute.
FAQ
What are the best 5G SIM only deals?
On 27 October 2026, Smarty 40GB was £7 a month with our deal button on a 1-month plan, and Smarty’s own site showed 32GB for £8 a month; both run on Three’s 5G network. On 28 October 2026, iD Mobile 50GB was £8 a month on a 12-month plan, also on Three. For O2 households, giffgaff’s 40GB was £8 a month on an 18-month plan, £144 over the full term, and its 25GB plan £10 a month, as listed on 1 November 2026; giffgaff says the 40GB for £8 plan is for sign-ups before 4 December 2026. Confirm the price on the retailer’s page before you buy.
How much is Smarty’s £8 plan?
On 1 November 2026, SMARTY listed its £8 plan with 32GB a month on a 1-month plan with unlimited UK calls and texts, and 40GB was £7 a month with our deal button. Prices can change, so confirm at checkout.
Does a 5G SIM guarantee 5G everywhere?
No. You need network 5G coverage, a compatible handset and plan permission.
Which network is Smarty on?
Smarty uses the Three network. giffgaff uses O2.
Can I keep my number on a cheap SIM?
Yes. Text PAC to 65075 from your current provider and port after the new SIM is active.
Should I buy Unlimited instead?
Only if you regularly need more than about 40–60GB. Otherwise mid-data is usually enough.
Do SIM prices change?
Yes. Introductory prices and plan line-ups can change at short notice. Order while the retailer page still shows the price you expect.
Do you earn commission?
Yes. SwitchSquid may earn a commission at no extra cost to you when you buy through the deal buttons on this page.
