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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 Classic

Data
Unlimited
(Unlimited speed included)
Allowances
Unlimited minutes
Unlimited texts
Contract
24 months
Total cost: £504
Price
£21per month
  • Price becomes £23.50 on 1 April 2026
  • Price becomes £26 on 1 April 2027
Free Disney+, Amazon Music, Prime, Audible, Cafeyn or McAfee Subscription (3 months)
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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: £599.76
Price
£24.99per month
  • Price becomes £27.49 on 1 April 2026
  • Price becomes £29.99 on 1 April 2027
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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: £803.76
Price
£33.49per month
  • Price becomes £35.99 on 1 April 2026
  • Price becomes £38.49 on 1 April 2027
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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
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Unlimited speed
5G+

SIM Only Classic

Data
Unlimited
(Unlimited speed included)
Allowances
Unlimited minutes
Unlimited texts
Contract
1 month
Price
£38per month
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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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Unlimited speed
5G+

SIM Only Classic

Data
300 GB
(Unlimited speed included)
Allowances
Unlimited minutes
Unlimited texts
Contract
12 months
Total cost: £192
Price
£16per month
  • Price becomes £18.50 on 1 April 2026
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logo
Unlimited speed
5G+

SIM Only Classic

Data
250 GB
(Unlimited speed included)
Allowances
Unlimited minutes
Unlimited texts
Contract
12 months
Total cost: £180
Price
£15per month
  • Price becomes £17.50 on 1 April 2026
Get deal
logo
Unlimited speed
5G+

SIM Only Classic

Data
250 GB
(Unlimited speed included)
Allowances
Unlimited minutes
Unlimited texts
Contract
24 months
Total cost: £648
Price
£27per month
  • Price becomes £29.50 on 1 April 2026
  • Price becomes £32 on 1 April 2027
Get deal
logo
Unlimited speed
5G+

SIM Only Classic

Data
150 GB
(Unlimited speed included)
Allowances
Unlimited minutes
Unlimited texts
Contract
24 months
Total cost: £408
Price
£17per month
  • Price becomes £19.50 on 1 April 2026
  • Price becomes £22 on 1 April 2027
Get deal

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