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O2 unlimited data sim only deals

O2 has a variety of unlimited data SIMs available on different contract lengths. If you need something different, O2 are have a range of other SIM only deals available:

O2 30-day SIM only dealsO2 12-month SIM only dealsO2 24-month SIM only dealsCheapest O2 SIM only dealsO2 Mobile Broadband SIM onlyO2 Tablet SIM onlyO2 5G SIMs
Our top pick
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Unlimited speed
5G+

SIM Only Plus Unlimited

Data
Unlimited
(Unlimited speed included)
Allowances
Unlimited minutes
Unlimited texts
Contract
24 months
Total cost: £551.76
Price
£22.99per month
  • Price becomes £25.49 on 1 April 2026
  • Price becomes £27.99 on 1 April 2027
Free Disney+, Amazon Music, Prime, Audible, Cafeyn or McAfee Subscription (6 months)
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Unlimited speed
5G+

SIM Only Classic

Data
Unlimited
(Unlimited speed included)
Allowances
Unlimited minutes
Unlimited texts
Contract
24 months
Total cost: £768
Price
£32per month
  • Price becomes £34.50 on 1 April 2026
  • Price becomes £37 on 1 April 2027
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logo
Unlimited speed
5G+

SIM Only Classic

Data
Unlimited
(Unlimited speed included)
Allowances
Unlimited minutes
Unlimited texts
Contract
12 months
Total cost: £420
Price
£35per month
  • Price becomes £37.50 on 1 April 2026
Get deal
logo
Unlimited speed
5G+

SIM Only Plus Unlimited

Data
Unlimited
(Unlimited speed included)
Allowances
Unlimited minutes
Unlimited texts
Contract
12 months
Total cost: £443.88
Price
£36.99per month
  • Price becomes £39.49 on 1 April 2026
Get deal
logo
Unlimited speed
5G+

SIM Only Classic

Data
Unlimited
(Unlimited speed included)
Allowances
Unlimited minutes
Unlimited texts
Contract
1 month
Price
£38per month
  • Price becomes £40.50 on 1 April 2026
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Unlimited speed
5G+

SIM Only Ultimate Unlimited

Data
Unlimited
(Unlimited speed included)
Allowances
Unlimited minutes
Unlimited texts
Contract
24 months
Total cost: £1019.76
Price
£42.49per month
  • Price becomes £44.99 on 1 April 2026
  • Price becomes £47.49 on 1 April 2027
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logo
Unlimited speed
5G+

SIM Only Ultimate Unlimited

Data
Unlimited
(Unlimited speed included)
Allowances
Unlimited minutes
Unlimited texts
Contract
12 months
Total cost: £545.88
Price
£45.49per month
  • Price becomes £47.99 on 1 April 2026
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