O2 SIM only deals: comparing their best plans in August

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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: 11th August 2022.
O2's best SIM only deals
Our best-rated O2 SIM only deal this month
From all the options O2 have got available this August on SIM only, we think this £20 24‑month deal is their best. For your £20 a month, you get 320GB data alongside unlimited minutes and texts:
While it's good enough to be in our pick of O2's best SIM only deals, other providers do still have similar plans for less, even ones that also use the O2 network. See who's offering it for less here:
Their 160GB for £20 SIM is another good option
If you need less data, another good deal on O2 at the moment is their £20 SIM only plan here, which includes 160GB data instead, plus unlimited minutes and texts:
It's definitely one of O2's best. But it's not market-leading. You can get a similar plan on other providers for less, even if you need your SIM to use the O2 network. Here's where you can beat it on other networks:
O2's 150GB for £24 plan is a good option too
For a smaller amount of data, our next best pick of O2 SIM only plans is their 12‑month £24 deal below, which gets you 150GB data and unlimited minutes and texts:
Even though it's in our pick of O2's best SIM only deals, you can actually beat it on price with other providers, including ones that also use the O2 network. See lower-priced networks' deals here:
Their £28 for unlimited data plan is a decent deal for August
For people who need even more data, O2 are also offering this £28 SIM, which includes unlimited data, unlimited minutes and texts on a 12‑month plan. It's another of their best deals:
While this is a good enough deal to make it into the best of O2's SIMs, you can beat it for price (even if you definitely want a provider that uses the O2 network). Here are other networks you can beat it on:
They're also offering 250GB for £28 on SIM only currently
For people who don't need that much data, you might like the £28 SIM only deal running on O2 at the moment. It's a 12‑month plan, which comes with 250GB data, unlimited minutes and texts too:
It's a good enough deal to get into O2's best SIMs but you can actually get a lower price for a similar plan elsewhere, even if you definitely want it to use the O2 network. See the networks with cheaper plans here:
£20 for 100GB is O2's next best SIM deal in August
If that'd be too much data for you, we'd say this is one of O2's best deals on SIM only this month too. It's a 12‑month plan, comes with 100GB data, unlimited minutes and texts for £20 a month:
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's which other networks can beat it:
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How O2's deals compare with other networks

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More about O2's SIM only plans
How O2's SIM only prices and benefits compare
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 tend to be one of the more expensive UK networks, but their larger data deals are usually a bit more competitive. There are a few cheaper providers who use the O2 network (including Sky Mobile, giffgaff and Tesco Mobile).
There’s a few extra benefits for being on O2. They’re the only main network to offer free inclusive EU roaming. They also offer extras on premium plans like worldwide roaming data passes and free subscriptions to entertainment services.
Useful link: Read our full O2 review
Useful information about O2’s SIM only deals
Your O2 SIM card will arrive between 1-4 working days depending on where in the UK you live. They also have premium delivery options. Your package will contain each size of SIM for any phone, and O2 also offer eSIMs.
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 get on a SIM only contract you’ll have to pass a credit check. This is because they don’t want their customers running up a massive bill they can’t pay. If this is an issue then you can pay up front for a payg 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