Checked SIM plans offering 100GB or more
Provider-checked starting prices from the shared comparison catalogue, not live quotes. Confirm promotions, eligibility, price changes and fees at checkout.
| Provider / plan | Data | Monthly | Minimum term | Network | Terms / checked |
|---|---|---|---|---|---|
| Talkmobile | 100GB | £4.98 | 12 months | Vodafone | 12-month contract; first three months cost £4.98, then £9.95 a month from 22 January 2027. Checked 22 October 2026 |
| Talkmobile | 150GB | £5.97 | 12 months | Vodafone | 12-month contract; first three months cost £5.97, then £11.95 a month from 22 January 2027. Checked 22 October 2026 |
| Lycamobile | 120GB | £10.00 | 30-day rolling | EE | 30-day PAYG bundle with no contractual commitment; renew or change after expiry. No promotional end price is printed in the tariff listing. Checked 22 October 2026 |
| SMARTY | 140GB | £12.00 | 30-day rolling | Three | Special offer: 140GB (standard 100GB). Offer end and renewal allowance: confirm with provider. Monthly rolling; no annual price rises advertised. Checked 22 October 2026 |
| SMARTY | 150GB | £15.00 | 30-day rolling | Three | Monthly rolling. No annual price rises advertised. Upfront charges: confirm with provider. Checked 22 October 2026 |
| giffgaff | 100GB | £15.00 | 18 months | O2 | 18-month contract. No mid-contract price rises advertised. No credit checks. Check roaming fair use and cancellation terms. Checked 22 October 2026 |
| 1pMobile | 100GB | £15.00 | 30-day rolling | EE | 30-day bundle with no long-term commitment. No promotional end price is printed for this bundle. Checked 22 October 2026 |
| RWG Mobile | 100GB | £15.00 | 30-day rolling | EE | 30-day plan with no contract. The page advertises no price rises. Checked 22 October 2026 |
| SMARTY | 200GB | £17.00 | 30-day rolling | Three | Monthly rolling. No annual price rises advertised. Upfront charges: confirm with provider. Checked 22 October 2026 |
| Tesco Mobile · 100GB · Standard | 100GB | £17.50 | 24 months | O2 | 24-month contract. Upfront charges unverified. Select the plan on the official SIM page; product-specific URLs may be stale. Standard price; confirm exact future price increases before ordering. Checked 2 November 2026 |
| ASDA Mobile | 100GB | £18.00 | 30-day rolling | Vodafone | Bundle lasts one calendar month without a long-term contract. It can be set to renew automatically; no promotional end price is printed. Checked 22 October 2026 |
| SMARTY | Unlimited | £20.00 | 30-day rolling | Three | Monthly rolling. No annual price rises advertised. Upfront charges: confirm with provider. Checked 22 October 2026 |
| VOXI | 300GB | £20.00 | 30-day rolling | Vodafone | 30-day rolling; cancel anytime. Price locked - your plan stays at the same monthly price 75GB/300GB displayed as 3x data versus 25GB/100GB; offer end and boost duration not stated in captured page Upfront charges: confirm with provider. Checked 22 October 2026 |
| giffgaff | 200GB | £20.00 | 18 months | O2 | 18-month contract. No mid-contract price rises advertised. No credit checks. Check roaming fair use and cancellation terms. Checked 22 October 2026 |
| giffgaff | 100GB | £20.00 | 30-day rolling | O2 | Monthly rolling. 5G included. Check roaming fair use, renewal prices and cancellation terms. Checked 22 October 2026 |
| 1pMobile | 200GB | £20.00 | 30-day rolling | EE | 30-day bundle with no long-term commitment. No promotional end price is printed for this bundle. Checked 22 October 2026 |
| Tesco Mobile · 100GB · Standard | 100GB | £20.00 | 12 months | O2 | 12-month contract. Upfront charges unverified. Select the plan on the official SIM page; product-specific URLs may be stale. Standard price; confirm exact future price increases before ordering. Checked 2 November 2026 |
| Sky Mobile | Unlimited | £21.00 | 24 months | O2 | 24-month minimum term: £21 a month for 12 months, then £25 a month. Prices may increase during the minimum term and the offer is lost if you switch data plan. Checked 22 October 2026 |
| Tesco Mobile · 250GB · Standard | 250GB | £22.50 | 24 months | O2 | 24-month contract. Upfront charges unverified. Select the plan on the official SIM page; product-specific URLs may be stale. Standard price; confirm exact future price increases before ordering. Checked 2 November 2026 |
| giffgaff | Unlimited | £25.00 | 18 months | O2 | 18-month contract. No mid-contract price rises advertised. No credit checks. Check roaming fair use and cancellation terms. Checked 22 October 2026 |
| giffgaff | 200GB | £25.00 | 30-day rolling | O2 | Monthly rolling. 5G included. Check roaming fair use, renewal prices and cancellation terms. Checked 22 October 2026 |
| 1pMobile | Unlimited | £25.00 | 30-day rolling | EE | 30-day bundle with no long-term commitment. Speeds may be reduced in busy locations after 500GB in a boost period. Checked 22 October 2026 |
| Tesco Mobile · Unlimited · Standard | Unlimited | £25.00 | 24 months | O2 | 24-month contract. Upfront charges unverified. Select the plan on the official SIM page; product-specific URLs may be stale. Standard price; confirm exact future price increases before ordering. Checked 2 November 2026 |
| Tesco Mobile · 250GB · Standard | 250GB | £25.00 | 12 months | O2 | 12-month contract. Upfront charges unverified. Select the plan on the official SIM page; product-specific URLs may be stale. Standard price; confirm exact future price increases before ordering. Checked 2 November 2026 |
| Vodafone | Unlimited | £26.00 | 24 months | Vodafone | 24-month Unlimited Plus plan. Monthly price rises to £28.50 on 1 April 2027 and £31 on 1 April 2028. Checked 22 October 2026 |
| Tesco Mobile · Unlimited · Standard | Unlimited | £30.00 | 12 months | O2 | 12-month contract. Upfront charges unverified. Select the plan on the official SIM page; product-specific URLs may be stale. Standard price; confirm exact future price increases before ordering. Checked 2 November 2026 |
| VOXI | Unlimited | £35.00 | 30-day rolling | Vodafone | 30-day rolling; price locked. eSIM available. European roaming requires a paid pass. Selected app data exclusions apply. Checked 22 October 2026 |
| giffgaff | Unlimited | £35.00 | 30-day rolling | O2 | Monthly rolling. 5G included. Check roaming fair use, renewal prices and cancellation terms. Checked 22 October 2026 |
Prices are advertised rates from each provider's own page on the date we checked, not live quotes. Clicking a name takes you to the provider.
Is 100GB enough for you?
Look at at least three complete billing months in your provider account. Include months when you travelled, streamed more video or used your phone as a hotspot. If your highest month is comfortably below 100GB, paying more for unlimited data may add little value.
Video quality, downloads and cloud backups change usage dramatically. Streaming on Wi-Fi does not normally consume your mobile allowance, but automatic switching to mobile data can. Keep a spending cap and usage alerts enabled.
Compare speed and tethering, not only gigabytes
A large data allowance is not a speed promise. Check any speed tier, local 4G and 5G reception and whether your handset supports the network's features. Predicted outdoor coverage is not a guarantee indoors.
Confirm hotspot permissions and fair-use terms before relying on a phone to connect a laptop or home router. Downloads, video meetings and updates on the connected device all count against your allowance.
Your UK allowance may not travel abroad
A 100GB or unlimited UK plan may have a much smaller roaming allowance, a daily charge or no included roaming at all. Check your destination, fair-use limit and charges before departure.
Compare the minimum term and scheduled price changes as well as the headline rate. Promotional prices and eligibility conditions must be confirmed on the provider's order page.
Frequently asked questions
Does this table include exactly 100GB plans?
Yes, alongside larger allowances and unlimited plans. Every displayed plan offers at least 100GB in the shared catalogue.
Is 100GB enough for home broadband replacement?
It depends on household use and local signal. Large downloads or streaming on several devices can exhaust it; check router permissions and performance first.
Is 100GB unlimited?
No. It is a finite allowance; unlimited plans are labelled separately and may still have fair-use conditions.
Can I use all 100GB abroad?
Do not assume so. Roaming limits and charges are set separately by the provider.
Will unused data roll over?
Only where the specific plan includes rollover. A large allowance does not imply that feature.
Official sources
Keep comparing
- Compare all SIM only plans
- 30-day rolling SIM contracts
- 12-month SIM contracts and costs
- Compare mobile networks
- SIM total-cost calculator
- Separate handset or phone contract?
- Work out how much mobile data you need
Listings are dated snapshots of providers' own pages, not live prices, and CompareDirect does not sell the products we list. We are not a credit broker or lender and give no financial advice.