Independent phone advice · No sponsored rankings · UK coverage · Updated August 2026
Reviewed 6 August 2026Plan snapshots checked against Mobiles.co.uk. Offers and availability can change without notice.
Advertising disclosure: Mobiles.co.uk buttons are paid advertising links. We may earn a commission at no extra cost to you; this never affects our rankings. How we stay independent.
SIM-only guide · Mobiles.co.uk offers

Keep the phone. Cut the monthly cost.

A focused shortlist of SIM-only plans sold through Mobiles.co.uk. Compare the allowance, commitment and catches before checking the live price.

Browse live SIM-only deals See our shortlist
All shopping buttons on this page go to Mobiles.co.uk. Prices can change.
Checked 6 August 2026

The useful shortlist

We selected distinct use cases from the live Mobiles.co.uk catalogue. The checkout page is definitive for price, cashback, coverage and availability.

£6per month
Best lighter-use plan

iD Mobile 25GB

One-month rolling SIM with 5G

Data25GB
Contract1 month
Best forEveryday use
  • Unlimited UK minutes and texts
  • Data rollover advertised
  • No annual price rise advertised

Watch for: 25GB is plenty for ordinary use but may feel tight if you stream video over mobile data every day.

View live Mobiles.co.uk deals
£10per month
Best high-data value

iD Mobile 120GB

12-month SIM with 5G

Data120GB
Contract12 months
CashbackMay apply
  • Unlimited UK minutes and texts
  • Large allowance for streaming or tethering
  • Mobiles.co.uk may list promotional cashback

Watch for: compare the headline monthly charge with the effective cost after cashback, and check how any claim process works.

View live Mobiles.co.uk deals
£8per month initially
Vodafone value pick

Vodafone 50GB

12-month SIM

Data50GB
Contract12 months
SpeedUp to 100Mbps
  • Unlimited UK minutes and texts
  • Vodafone benefits advertised
  • Promotional cashback may reduce effective cost

Watch for: the monthly price is scheduled to rise during the agreement; check the dated price schedule and total cost before ordering.

View live Mobiles.co.uk deals
£15per month
Best unlimited option

iD Mobile Unlimited

12-month unlimited-data SIM with 5G

DataUnlimited
Contract12 months
Best forMaximum use
  • Unlimited UK minutes and texts
  • Useful for frequent streaming or tethering
  • Promotional cashback may be available

Watch for: unlimited is poor value if your real monthly use is modest. Check the last three months in your phone settings first.

View live Mobiles.co.uk deals

Plan snapshot checked against the Mobiles.co.uk SIM-only catalogue on 6 August 2026. Prices, doubled-data offers, cashback and stock can change.

Start with your usage

How much data do you need?

Buying the biggest allowance is not automatically good value. Look at your phone's mobile-data history before choosing.

1

Up to 10GB

Calls, messaging, maps and light browsing—mostly connected to Wi-Fi.

2

20–50GB

The sensible range for social media, music and occasional video.

3

100GB+

Frequent streaming, hotspot use or fewer dependable Wi-Fi connections.

4

Unlimited

Heavy streaming and tethering where you do not want to monitor usage.

Read the whole price

Three numbers to check

Headline monthly charge

What leaves your account each month before considering a promotion or price rise.

Effective cost after cashback

Useful for comparison, but only if you understand whether cashback is automatic or must be claimed.

Total contract cost

The clearest comparison once scheduled price increases and the full commitment are included.

Before you switch

Frequently asked questions

Do all shopping buttons go to Mobiles.co.uk?

Yes. Mobiles.co.uk is the only retailer linked by shopping buttons on this page. iD Mobile and Vodafone are the networks supplying the plans shown inside its catalogue.

Can I keep my mobile number?

Yes. Ask your current network for a PAC and give it to the new network during the switch. Do not cancel your old service before the number transfer completes.

Should I choose one month or 12 months?

Choose one month when flexibility matters. A longer agreement can unlock more data or cashback, but check price increases and the full contract cost.

Are these positions paid?

No. Mobiles.co.uk cannot pay to move an option up the shortlist. CompareAMobile may earn commission when a reader uses a shopping link, but this never changes our ordering or guidance.

Complete the setup

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