£21.00 a month
£0.00 upfront · 12-month contract
Rises to £23.50 from 1 Apr 2027
£267.00 estimated minimum-term cost (listed rises included)
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Compare monthly voice-SIM contracts from O2, giffgaff, iD Mobile and Mobiles.co.uk. Prepaid bundles, travel eSIMs and data-only plans are not included yet.
147 offers · Last refreshed 20 Oct 2026, 13:09
£21.00 a month
£0.00 upfront · 12-month contract
Rises to £23.50 from 1 Apr 2027
£267.00 estimated minimum-term cost (listed rises included)
£114.00 cashback advertised: Cashback by redemption. Not deducted from our costs; eligibility and retailer terms apply.
20GB data (5G)
Unlimited minutes · Unlimited texts
SIM Only Plus 20GB · Sold by O2
6 months Free Disney+
£22.99 a month
£0.00 upfront · 24-month contract
Rises to £25.49 from 1 Apr 2027
Rises to £27.99 from 1 Apr 2028
£611.76 estimated minimum-term cost (listed rises included)
3GB data (5G)
Unlimited minutes · Unlimited texts
SIM Only Plus 3GB · Sold by O2
6 months Free Disney+
£22.99 a month
£0.00 upfront · 12-month contract
Rises to £25.49 from 1 Apr 2027
£290.88 estimated minimum-term cost (listed rises included)
Unlimited data (5G)
Unlimited minutes · Unlimited texts
SIM Only Classic · Sold by O2
3 months Free Disney+
£23.00 a month
£0.00 upfront · 24-month contract
Rises to £25.50 from 1 Apr 2027
Rises to £28.00 from 1 Apr 2028
£612.00 estimated minimum-term cost (listed rises included)
50GB data (5G)
Unlimited minutes · Unlimited texts
SIM Only Classic · Sold by O2
3 months Free Disney+
£24.00 a month
£0.00 upfront · 24-month contract
Rises to £26.50 from 1 Apr 2027
Rises to £29.00 from 1 Apr 2028
£636.00 estimated minimum-term cost (listed rises included)
20GB data (5G)
Unlimited minutes · Unlimited texts
SIM Only Classic · Sold by O2
3 months Free Disney+
£24.00 a month
£0.00 upfront · 12-month contract
Rises to £26.50 from 1 Apr 2027
£303.00 estimated minimum-term cost (listed rises included)
3GB data (5G)
Unlimited minutes · Unlimited texts
SIM Only Mini 3GB · Sold by O2
6 months Free Disney+
£24.00 a month
£0.00 upfront · 1-month plan
£24.00 estimated first-month cost
This is not an annual cost. Check renewal and cancellation terms.
£24.99 a month
£0.00 upfront · 24-month contract
Rises to £27.49 from 1 Apr 2027
Rises to £29.99 from 1 Apr 2028
£659.76 estimated minimum-term cost (listed rises included)
£25.00 a month
£0.00 upfront · 18-month contract
£450.00 estimated minimum-term cost
20GB data (5G)
Unlimited minutes · Unlimited texts
SIM Only Plus 20GB · Sold by O2
6 months Free Disney+
£25.99 a month
£0.00 upfront · 12-month contract
Rises to £28.49 from 1 Apr 2027
£326.88 estimated minimum-term cost (listed rises included)
£26.99 a month
£0.00 upfront · 24-month contract
Rises to £29.49 from 1 Apr 2027
Rises to £31.99 from 1 Apr 2028
£707.76 estimated minimum-term cost (listed rises included)
100GB data (5G)
Unlimited minutes · Unlimited texts
SIM Only Plus 100GB · Sold by O2
6 months Free Disney+
£26.99 a month
£0.00 upfront · 24-month contract
Rises to £29.49 from 1 Apr 2027
Rises to £31.99 from 1 Apr 2028
£707.76 estimated minimum-term cost (listed rises included)
20GB data (5G)
Unlimited minutes · Unlimited texts
SIM Only Mini 20GB · Sold by O2
6 months Free Disney+
£27.00 a month
£0.00 upfront · 1-month plan
£27.00 estimated first-month cost
This is not an annual cost. Check renewal and cancellation terms.
£27.99 a month
£0.00 upfront · 24-month contract
Rises to £30.49 from 1 Apr 2027
Rises to £32.99 from 1 Apr 2028
£731.76 estimated minimum-term cost (listed rises included)
£27.99 a month
£0.00 upfront · 12-month contract
Rises to £30.49 from 1 Apr 2027
£350.88 estimated minimum-term cost (listed rises included)
100GB data (5G)
Unlimited minutes · Unlimited texts
SIM Only Classic · Sold by O2
3 months Free Disney+
£28.00 a month
£0.00 upfront · 12-month contract
Rises to £30.50 from 1 Apr 2027
£351.00 estimated minimum-term cost (listed rises included)
£29.99 a month
£0.00 upfront · 24-month contract
Rises to £32.49 from 1 Apr 2027
Rises to £34.99 from 1 Apr 2028
£779.76 estimated minimum-term cost (listed rises included)
100GB data (5G)
Unlimited minutes · Unlimited texts
SIM Only Plus 100GB · Sold by O2
6 months Free Disney+
£29.99 a month
£0.00 upfront · 12-month contract
Rises to £32.49 from 1 Apr 2027
£374.88 estimated minimum-term cost (listed rises included)
£30.99 a month
£0.00 upfront · 12-month contract
Rises to £33.49 from 1 Apr 2027
£386.88 estimated minimum-term cost (listed rises included)
Before you switch
Monthly sorting and the price cap use the standard price after any introductory discount, before future rises. Average cost is the estimated minimum-term cost divided by its length, not a guaranteed ongoing bill. Cashback is never deducted. Some retailers sell the same plan.
Check coverage where you live and work, your phone’s compatibility, minimum term, cancellation rules and any credit check. A one-month plan cost is not a yearly cost. Listed rises are included in our estimate; missing rises do not mean a price freeze. Check current prices, renewal terms and eligibility with the retailer before applying.
We may earn commission through retailer links. Saved SIM plans have their own comparison group, separate from phones. SIM-only deals are not yet included in the phone-finder assistant.
SIM-only or a phone contract? · How to keep your number when switching