SIM only · 100GB+
100GB SIM only deals
The cheapest SIM with at least 100GB on every UK network, ranked by the true cost over 24 months. Heavy streaming, hotspot use and rarely thinking about data.
bemobiles tips
Is 100GB enough for me?
Heavy streaming, hotspot use and rarely thinking about data. Use our data calculator to check.
Should I pick 30-day or 12 months?
A 30-day plan costs about the same and lets you switch whenever prices drop.
Which networks don’t rise?
giffgaff, SMARTY, Lebara, Lycamobile, VOXI and iD Mobile (SIM only).
No price rise- Runs on Three
- 30-day rolling plan
- No credit check
- EU roaming included, 12 GB
£10 a month
Get this dealSMARTY review →Live price, checked several times a day.
100GB SIM only deals: every network ranked
| # | Network | Data | Contract | Monthly | Annual rise | 24 months, rises included | |
|---|---|---|---|---|---|---|---|
| 1 |  Talkmobile | 100GB | 30 days | £8.95 | Check at sign-up | £214.80 | Get deal |
| 2 |  iD Mobile | 108GB | 30 days | £9 | None on SIM only; phone plans +£1.80 | £216 | Get deal |
| 3 | SMARTY | 100GB | 30 days | £10 | No annual rise | £240 | Get deal |
| 4 |  Three | 100GB | 12 months | £10 | +£1.80 to £2.30 every April by data | £285.60 | Get deal |
| 5 |  VOXI | 100GB | 30 days | £12 | No annual rise | £288 | Get deal |
| 6 |  Asda Mobile | 100GB | 12 months | £12 | Check at sign-up | £288 | Get deal |
| 7 |  O2 | 120GB | 30 days | £12 | +£2.50 every April | £348 | Get deal |
| 8 |  Vodafone | 100GB | 12 months | £12 | +£2.50 every April (Basics +£1.50) | £348 | Get deal |
| 9 |  Tesco Mobile | 100GB | 24 months | £14 | Fixed rise of about 6% every April | £356.16 | Get deal |
| 10 |  giffgaff | 100GB | 18 months | £15 | No annual rise | £360 | Get deal |
| 11 |  Lebara | 100GB | 12 months | £18 | No annual rise | £432 | Get deal |
| 12 |  Lycamobile | Unlimited | 24 months | £18 | No annual rise announced | £432 | Get deal |
| 13 |  Sky Mobile | Unlimited | 24 months | £20 | +£1.50 from Feb 2026, not fixed in contract | £480 | Get deal |
Cheapest plan per network matching this page, checked 27 October 2026. “24 months” adds each network’s April rise for a plan starting this month; on 30-day plans you can leave before a rise.
Getting the best 100GB deal
Every network on the list may give you more than 100GB for the cheapest price — the data column shows what you actually get. Compare the 24-month column: a network that is £1 cheaper today can cost more by the second year once its April rise kicks in. How much data do I need?
All matching deals, live
FAQ
Common questions
What is the cheapest 100GB SIM?
The first row of the table today, ranked by the 24-month cost.
How long does 100GB last?
Roughly 67 hours of standard video or 1000 hours of browsing a month.
Can I get more data for the same price?
Often — budget networks frequently include more data than the big four at the same price.