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- Some competitive phone plans
- Useful perks
- Good for roaming
- Improved customer service
- SIM-only plans still expensive
- Not leading on performance
- Still too many complaints and long waits on calls
Now part of a joint venture with Virgin Media, O2 is one of the UK’s big three mobile networks, alongside the recently merged VodafoneThree and the BT-owned EE. It’s a popular brand with millions of users, while providing the network infrastructure for its budget offshoot, Giffgaff, plus Tesco Mobile and Sky Mobile too.
The major networks haven’t done as well as you might expect in this year’s Mobile Network Awards, with the smaller virtual networks – including Giffgaff – sweeping up most of the prizes. O2 has much the same problems as Three in the survey, with too many customers feeling dissatisfied with the brand’s customer service, performance and value for money, not helped by some high pricing on O2’s part.
And while O2 has fared better than Three in some award categories, particularly multi-user plans, it still finds itself in the bottom three of our Overall results table, not to mention the Most Recommended. While 40% of the customers we spoke to would recommend O2, 17% would not, while 43% have no strong feelings one way or the other; a disappointing result.
O2 review: What do you get?
O2’s flexible when it comes to its monthly phone contracts. It offers a decent range of budget, mid-range and flagship smartphones on ready-made, 36-month contracts, or you can roll your own with your chosen mix of upfront payment, contract term and data allowance. You can keep your monthly costs low by spending more upfront and opting for the maximum three years, or pay off the phone faster by reducing the term to 24 months or even just one year.
Some contracts come with extras, like a three month subscription to Amazon Prime, Amazon Music, Audible or Disney+, and you have the option to switch phone after a minimum 90 days using O2’s Switch Up feature. This is included on specific phones and Plus or Ultimate Plans at no extra cost.
These plans can be relatively expensive. Even on a 36-month plan, an iPhone 17 with 125GB of data is – at the time of writing – going to cost you £54.24/mth plus £30 upfront. Reduce the term to 24 months, and you’re looking at £65.86/mth. On Three, your monthly fee would be ten pounds lower with 150GB of data, while iD Mobile would be even cheaper. However, O2 does get the odd great deal. Buy a Samsung Galaxy S25 on a similar 125GB plan, and you’ll currently spend £6.29 less per month on O2 than you would on Three.
On its SIM-only contracts, O2 offers them in Classic, Plus and Ultimate flavours, with the Plus plans bringing in inclusive roaming in 75 destinations plus six months of Amazon Prime or Disney+. Head upscale to one of the Ultimate plans, and your roaming range expands to take in 123 destinations. Customers with an existing Virgin Media broadband contract can also get extra data and free roaming on an O2 package, not to mention a potential boost to their broadband speeds.
O2’s deals are now generally slightly cheaper than their EE or Vodafone equivalents. Its Unlimited Plus contract is currently £21.99/mth on a 24-mionth contract, while Vodafone’s equivalent is £24 and EE’s £23. All the same, the likes of Smarty, Giffgaff and iD Mobile will give you unlimited data for less.
Perhaps this all explains why O2 comes third from bottom in our Value awards category. Just over a third (34%) of users told our survey that they were very satisfied with the value they were getting from their mobile network, though half said they were satisfied. 4% were actively dissatisfied, placing O2 below EE and iD Mobile but above Vodafone and Three. There are worse positions to be in, but O2 is a long way from the prizes here.
O2 review: Customer service
It’s a similar story with customer service. When we asked how well the mobile provider handles complaints, 73% of O2 customers who’d had a complaint said they were satisfied, but 7% were dissatisfied, resulting in a net score of 66%. That puts O2 ahead of Three and iD Mobile, but a long way behind leaders Tesco Mobile and Giffgaff, with net scores of 87% and 88%.
There’s mixed news for O2 from Ofcom’s latest customer service research. The brand has lower than average levels of customer satisfaction with its service, not to mention reception or signal strength and value for money. However, 65% of customers said they were satisfied with O2’s complaint handling, even if O2’s call waiting times are longer than the industry average, while it’s getting more complaints per 100,000 subscribers than any other brand; 23 against an average of 12. There’s definitely room for improvement.
O2 review: Coverage, reliability and speed
O2 isn’t the worst of the big networks for reliability according to our survey. Its scores are relatively low for browsing, but better for streaming and online gaming than either Vodafone or Three. However, Tesco Mobile and Sky Mobile do significantly better according to their customers, even though all three run on the same core network.
While 86% of customers said they were satisfied or very satisfied with O2’s mobile data speeds, 79% were confident or very confident they could maintain a fast enough connection for more demanding tasks in a busy area. Though these figures seem high, the net average result leaves O2 languishing near the bottom of our performance table, with only Three getting lower scores.
The latest figures from Rootmetrics show that O2’s speeds and 5G coverage have improved over its 2024 results, but that O2 remains the fourth fastest of the major networks (separating Vodafone and Three), with a UK median download speed of 36.2Mbits/sec. It’s the only network with a median 5G download speed below 100Mbits/sec. With EE and Three getting well over 200Mbits/sec, there’s a real sense that O2 is struggling to catch-up.
O2 review: Roaming
O2 goes further in some areas than rivals, with free EU roaming on all contracts subject to a reasonable 25GB fair usage policy. The Plus plans go further, covering 75 destinations, including Australia, Mexico, Canada and the USA. The Ultimate plans take that up a notch to reach 123 worldwide destinations, including popular countries in Asia, Africa and South and Central America. Those on the Classic plans can use their allowance with an O2 Travel bolt-on, for a fixed price of £7 per day. Outside of this, costs soon rack up, reaching £3 per minute, and £1 per text in the U.S. plus data roaming bundles, which you need to buy before you travel, starting at 1GB for £6.
O2’s users are generally impressed with its approach to roaming, and the brand came second in this category in this year’s survey, with only Tesco Mobile scoring higher. 86% of users were either satisfied or very satisfied with the value of their roaming services, and only 6% were dissatisfied or very dissatisfied.
O2 review: Other features, services and spending caps
O2 has some other useful features, including savings if you add a second connection to your account and a data rollover where unused data is shifted to your next month’s allowance. O2 also reduces your monthly charge once you’ve paid off your device automatically, which isn’t something you can take for granted elsewhere.
What makes O2 extra tempting, though, is its Priority perks, earning you special treatment or priority booking at O2 venues, plus a selection of other perks. Sky Mobile and Vodafone did better in the Perks category of our survey, but O2 had more very satisfied customers on this point than EE, though 2% said they were dissatisfied, bringing the overall score down and losing O2 a shot at the runner-up award.
O2 review: Verdict
O2’s perks and features make it a tempting option, and it does have some good deals on phone contracts and SIM-only plans. Customer service scores are mostly headed in the right direction, and it’s one of the best mobile networks for travel, with free EU roaming on every plan. All the same, it’s not one of the top-ranked networks for speeds or reliability, and many of its plans are still expensive for what you get. It’s a solid network, but it’ll take more than that before it starts winning our awards.
