What is the best SIM only deal in the UK?

The best SIM only deal depends on your data needs and whether you want flexibility or the lowest price. For unlimited data on a 30-day rolling plan, Chattr and Smarty consistently offer the best value. For small data allowances, Lebara and giffgaff start from just £5 per month. For no annual price rises, iD Mobile is a strong option.

Can I get a SIM only deal with no contract?

Yes. Most networks offer 30-day rolling SIM only plans with no long-term commitment. Chattr, giffgaff, Lebara, and iD Mobile all offer 30-day plans you can cancel or change with 30 days notice. These plans cost slightly more per month than 12 or 24-month deals but give you full flexibility.

Can I keep my number when switching to SIM only?

Yes. Text PAC to 65075 and your current network must provide your PAC code within two minutes. Give the code to your new network when signing up and your number transfers within one working day. You will not lose your number during the switch.

Is SIM only cheaper than a phone contract?

Yes, significantly. SIM only plans are cheaper because you are not paying off a handset. For equivalent data, a SIM only plan typically costs £15 to £30 less per month than a phone contract. Over a year that is £180 to £360 saved.

SIM only deals UK 2026

Stop overpaying foryour SIM plan

Compare SIM only deals from leading UK networks. Find the best plan for your data needs, budget, and contract preference.

Secure data

Save up to £360/year

Switch in minutes

We found 15 options for you

OUR PICK

Chattr Unlimited Data

Monthly price

£20

Unlimited data, calls and texts

O2 priority rewards

30-day rolling contract

View Deal

Lebara Unlimited Data

🇦🇺🇦🇹🇧🇩🇧🇪🇧🇷🇧🇬🇨🇦🇨🇱🇨🇳🇨🇴🇭🇷🇨🇾🇨🇿🇩🇰🇪🇪🇫🇮🇫🇷🇩🇪🇬🇷🇬🇵🇭🇰🇭🇺🇮🇸🇮🇪🇮🇹🇯🇵🇱🇻🇱🇹🇱🇺🇲🇾🇲🇹🇲🇽🇲🇳🇳🇱🇳🇿🇳🇴🇵🇪🇵🇱🇵🇹🇵🇷🇷🇴🇸🇬🇸🇰🇸🇮🇰🇷🇪🇸🇸🇪🇨🇭🇹🇼🇹🇭🇺🇦🇺🇸

Monthly price

£30

Unlimited minutes to 50+ countries

1000 extra minutes to India

30-day rolling contract

View Deal

Asda Mobile Unlimited Data

Monthly price

£19

Unlimited data

24-month contract

Asda rewards

View Deal

Lebara 100GB Plan

Monthly price

£20

Unlimited minutes to 50+ countries

1000 extra minutes to India

30-day rolling contract

View Deal

Asda Mobile 100GB Plan

Monthly price

£17

100GB data

24-month contract

Asda rewards

View Deal

Chattr 50GB Plan

Monthly price

£15

Unlimited calls and texts

O2 priority rewards

30-day rolling contract

View Deal

Lebara 50GB Plan

Monthly price

£15

Unlimited UK minutes and texts

500 minutes to 50+ countries

30-day rolling contract

View Deal

giffgaff 75GB Plan

Monthly price

£12

75GB data

Unlimited calls and texts

30-day rolling contract

View Deal

iD Mobile 80GB Plan

Monthly price

£10

No annual price rises

Unlimited calls and texts

12-month contract

View Deal

giffgaff 40GB Plan

Monthly price

£10

40GB data

Unlimited calls and texts

30-day rolling contract

View Deal

iD Mobile 30GB Plan

Monthly price

£8

No annual price rises

Unlimited calls and texts

30-day rolling contract

View Deal

giffgaff 5GB Plan

Monthly price

£8

5GB data

Unlimited calls and texts

30-day rolling contract

View Deal

iD Mobile 15GB Plan

Monthly price

£7

No annual price rises

Unlimited calls and texts

12-month contract

View Deal

Asda Mobile 10GB Plan

Monthly price

£7

10GB data

24-month contract

Asda rewards

View Deal

Lebara 5GB Plan

Monthly price

£5

1000 UK minutes and texts

100 minutes to 50+ countries

30-day rolling contract

View Deal

Looking for something more specific?

All SIM deals Unlimited data SIMs 5G SIM only deals No contract SIMs Pay as you go SIMs Family SIM deals Student SIMs Kids SIMs Data only SIMs iPad and tablet SIMs Phone deals Broadband deals

Not sure which to choose?

Get in touch and we will help you find the best SIM plan for your needs.

Talk to an expert