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O2 SIM only deals: comparing their best plans in May

O2 logo with a SIM cardVisit O2.co.uk

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We look at whether O2's current best SIM only plans are decent value compared to all their competitor mobile networks in the UK. SIM Sherpa is your trusty guide. Last updated: 23rd May 2024.

O2's best SIM only deals

The best SIM only deal on O2 this month

O2 SIM only deal
SIM only
just
£32.99
a month
🛈 Monthly price will increase each April by the Retail Price Index rate of inflation published in February + 3.9%

Unlimited mins and unlimited data See full deal

at o2.co.uk
(opens in new window)

Out of all the SIM only plans available this May on O2, we'd say their best value deal is their 24‑month SIM below, which gets you unlimited data, plus unlimited minutes and texts for £32.99 a month:

O2 logo

Unlimited minutes + Unlimited texts + 0MB Unlimited data (5G) = £0 £16.50 a month for 6 months, then £32.99 (24‑month contract)
See full deal

🛈 Monthly price will increase each April by the Retail Price Index rate of inflation published in February + 3.9%

In comparison to the rest of O2's current SIM only plans, it's one of the best. But it is beatable on price, even if you're set on joining a provider that uses the O2 network. Here are other networks you can beat it on:

Vodafone logo

Unlimited minutes + Unlimited texts + 0MB Unlimited data (5G) = £0 £26 a month (12‑month contract)
Cashback symbol £84 cashback (automatic, no need to claim)
See full deal

🛈 Monthly price + out of bundle charges will increase every April by the Consumer Price Index rate of inflation + 3.9%
ASDA Mobile logo

Unlimited minutes + Unlimited texts + 0MB Unlimited data (3G) = £0 £20 a month (1‑month plan, no contract)
See full deal

2 Mbps speed cap
🛈 ASDA reserve the right to increase the cost of this plan annually with one month's notice
Three logo

Unlimited minutes + Unlimited texts + 0MB Unlimited data (5G) = £22 £20 a month (24‑month contract)
See full deal

🛈 Monthly price will increase each April by the Consumer Price Index rate of inflation published in December + 3.9%
Tesco Mobile logo

Unlimited minutes + Unlimited texts + 0MB Unlimited data (5G) = £0 £25 a month (24‑month contract)
See full deal

🛈 Monthly price will increase each April by the Consumer Price Index rate of inflation published in January + 3.9%

Or their £20.99 for 30GB SIM plan is worth a look too

O2 SIM only deal
SIM only
just
£20.99
a month
🛈 Monthly price will increase each April by the Retail Price Index rate of inflation published in February + 3.9%

Unlimited mins and 30GB data See full deal

at o2.co.uk
(opens in new window)

If you need less data, you might like the £20.99 SIM only deal running on O2 at the moment. It's a 24‑month plan, which comes with 30GB data, unlimited minutes and texts too:

O2 logo

Unlimited minutes + Unlimited texts + 0MB 30GB data (5G) = £0 £20.99 a month (24‑month contract)
See full deal

🛈 Monthly price will increase each April by the Retail Price Index rate of inflation published in February + 3.9%

It does enough to get into our pick of O2's best SIMs but that doesn't mean it's unbeatable on price. Other providers (even ones that use the O2 network) can beat it. See the networks with cheaper plans here:

Three logo

Unlimited minutes + Unlimited texts + 0MB 30GB data (5G) = £16 £8 a month (12‑month contract)
See full deal

🛈 Monthly price will increase each April by the Consumer Price Index rate of inflation published in December + 3.9%
Vodafone logo

Unlimited minutes + Unlimited texts + 25GB 30GB data (4G) = £0 £8 a month (12‑month contract)
See full deal

No roaming, 4G- or WiFi calling
🛈 Monthly price will increase each April by the Consumer Price Index rate of inflation published in January + 3.9%
VOXI logo

Unlimited minutes + Unlimited texts + 15GB 30GB data (5G) = £0 £10 a month (1‑month plan, no contract)
See full deal

🛈 VOXI reserve the right to increase the cost of this plan annually with one month's notice
Coop Mobile logo

Unlimited minutes + Unlimited texts + 10GB 30GB data (5G) = £0 £13 a month (1‑month contract)
See full deal

🛈 Monthly price will increase each March by the Consumer Price Index rate of inflation published in January + 3.9%
ASDA Mobile logo

Unlimited minutes + Unlimited texts + 0MB Unlimited data (3G) = £0 £20 a month (1‑month plan, no contract)
See full deal

2 Mbps speed cap
🛈 ASDA reserve the right to increase the cost of this plan annually with one month's notice

O2 are also offering 150GB for £23.99 on SIM only

O2 SIM only deal
SIM only
just
£23.99
a month
🛈 Monthly price will increase each April by the Retail Price Index rate of inflation published in February + 3.9%

Unlimited mins and 150GB data See full deal

at o2.co.uk
(opens in new window)

To get more data, we'd say this is one of O2's best deals on SIM only this month too. It's a 24‑month plan, comes with 150GB data, unlimited minutes and texts for £23.99 a month:

O2 logo

Unlimited minutes + Unlimited texts + 0MB 150GB data (5G) = £0 £23.99 a month (24‑month contract)
See full deal

🛈 Monthly price will increase each April by the Retail Price Index rate of inflation published in February + 3.9%

It isn't actually the cheapest 150GB data or more SIM available overall this month but if you definitely need your plan to use the O2 network, it is the lowest cost option. Here's which other networks can beat it:

Vodafone logo

Unlimited minutes + Unlimited texts + 0MB Unlimited data (5G) = £0 £26 a month (12‑month contract)
Cashback symbol £84 cashback (automatic, no need to claim)
See full deal

🛈 Monthly price + out of bundle charges will increase every April by the Consumer Price Index rate of inflation + 3.9%
ASDA Mobile logo

Unlimited minutes + Unlimited texts + 0MB Unlimited data (3G) = £0 £20 a month (1‑month plan, no contract)
See full deal

2 Mbps speed cap
🛈 ASDA reserve the right to increase the cost of this plan annually with one month's notice
Three logo

Unlimited minutes + Unlimited texts + 0MB Unlimited data (5G) = £22 £20 a month (24‑month contract)
See full deal

🛈 Monthly price will increase each April by the Consumer Price Index rate of inflation published in December + 3.9%

Compare all SIM only plans

Compare deals from all networks

How O2's deals compare with other networks

SIM card with magnifying glass

Networks

Providers:

1p Mobile logo
Three logo
ASDA logo
Boshhh Mobile logo
Coop Mobile logo
EE logo
Genius logo
giffgaff logo
Honest logo
ID logo
IQ logo
Lebara logo
Lycamobile logo
O2 logo
SMARTY logo
Sky logo
spusu logo
Talkhome logo
Talkmobile logo
Tesco logo
Vodafone logo
VOXI logo

Plan

Data: (0MB+)

Minutes: (0+)

Contract

Maximum length: (Any)

Added features

More about O2's SIM only plans

O2’s SIM only prices and benefits compared

Rating stars and O2 logo

What we generally think about O2Read our full review

at simsherpa.com
(opens in new window)

In our full review of the O2 network we said we liked their brilliant call signal (3G/2G) coverage, their good 5G coverage and their great WiFi hotspot scheme. We also like their WiFi calling and 4G calling.

You have the choice of 1-month, 12-month and 24-month contracts. Their 24-month contracts are usually much cheaper per month, but it’s best to check their current deals for the best possible offer.

O2’s deals tend to be some of the most expensive of all networks, but they’re a bit more competitive on big data deals. There are some smaller providers on O2’s network who offer better value SIM only deals.

They’re also the only main UK network to still offer inclusive EU roaming on all plans. And you can get extras on premium plans, such as subscriptions to entertainment services and worldwide roaming data passes.

Useful link: Read our full O2 review

Other things to know about O2’s SIM only deals

O2 coverage checker screenshot

Check signal before you buy your planCheck yours now

at O2.co.uk
(opens in new window)

You’ll get your O2 SIM card between 1-4 working days after ordering (depends on your location). And there are premium delivery options too. You’ll receive each size of SIM for any phone. Or you can take an eSIM.

When your SIM arrives, you have 14 days to return it and get a full refund if you’re not satisfied. This will also cancel your contract. Here’s how you do that.

To prevent customers racking up huge bills they can’t pay, O2 make you pass a credit check to join them. If you have a poor or no credit history you can still join O2 on a PAYG monthly bundle instead.

And if you’re switching to O2 from another network you can keep your number by requesting a PAC from your old provider and giving it to O2 at any point. Here’s how you do that.

Useful link: Compare all O2 SIMs

Other O2 guides