
O2 has now had a 4G network for years and it’s been busy in that time, bringing speedy 4G coverage to around 99% of the UK population indoors, with that figure growing all the time, while 5G coverage is rapidly increasing too, reaching at least 76% of UK premises outdoors at the time of writing according to Ofcom.
But is O2 the right network for you? To answer that we need to look at more than just coverage, which is why this review addresses plans, tethering, roaming, extra perks and more, as well as the availability of 4G and 5G.
So read on to get a clear picture of whether O2 is your ideal network. And if you’re ever looking for a new network in future, make sure to check back here, as we’ll be keeping this page updated as O2’s network evolves.
|
Pros |
Cons |
|---|---|
|
Free EU roaming |
Fewer extras than some rivals |
|
O2 Priority |
Lower speeds than main rivals |
Our Rating
| Table of Contents |
|
Network Type |
Coverage by population |
|---|---|
|
5G |
At least 76% |
|
4G |
99% |
|
3G |
N/A |
|
2G |
99% |
| Check O2 Coverage | |
O2 launched its 5G service on October 17th, 2019. It initially launched in six cities but its 5G service is now available in many more locations. At the time of writing you can get O2 5G in at least 76% of UK premises outdoors according to Ofcom.
If you don’t have O2 5G where you are yet, it should be worth waiting for, as it is far faster than 4G, so you can download and upload files faster and stream in higher quality. More excitingly, 5G could open up whole new use cases, such as truly smart cities and things we haven’t even envisaged yet.
To take advantage of its power though you’ll need a 5G phone, but almost every modern smartphone now supports 5G.
O2’s 4G coverage currently rivals Vodafone's, EE's and Three’s at 99% or more, based on the latest available information at the time of writing. So you can be confident that across the UK as a whole you’ll get competitive coverage on O2, though it’s always worth checking what coverage is like in your area before signing up to a network.
4G from O2 is now available in thousands of UK towns, cities, and villages, so if you live in a remotely urban area then you’ll more likely than not be able to get O2 4G, and many rural areas will have access too.
As of April 2026, O2’s 3G network has mostly been switched off, so that the spectrum can be repurposed for faster 4G and 5G services.
O2 offers Pay Monthly phones, along with SIM Only plans and Data Only plans, all of which you can see details of below. The network also offers Pay As You Go (detailed further down), and mobile broadband plans.
|
|
Mobile Phones |
SIM Only |
Data Only |
|---|---|---|---|
|
Plans Available |
✔ |
✔ |
✔ |
|
Max Data |
Unlimited |
Unlimited |
Unlimited |
|
Contract lengths |
3-36 months |
1, 12 or 24 months |
1, 12 or 24 months |
|
|
|
10 GB data Unlimited mins Unlimited texts 12 Month Contract |
£7.00 a month |
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40 GB data Unlimited mins Unlimited texts 12 Month Contract |
£8.00 a month |
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50 GB data Unlimited mins Unlimited texts 12 Month Contract |
£9.00 a month |
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|
10 GB data Unlimited mins Unlimited texts 1 Month Contract |
£10.00 a month |
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|
75 GB data Unlimited mins Unlimited texts 12 Month Contract |
£10.00 a month |
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| View All O2 Sim Only Deals | |||||||||||
O2 has a range of Pay Monthly, SIM Only and Pay As You Go plans available. 5G is also available at no extra cost.
O2’s Pay Monthly plans are flexible, as while they default to 36 months in duration you can also edit them, choosing anything from as little as 3 months, with prices changing accordingly. You can also adjust how much you’re prepared to pay upfront and how much data you want (up to a maximum of unlimited data). They also allow tethering, and you can use as much of your data allowance for that as you want.
O2’s SIM Only plans come in at 24 months, 12 months or just 1 month long. They also come with a lot of data, topping out at unlimited. As with Pay Monthly, they also allow tethering, and you can use as much of your data allowance for that as you want.
Both phone and SIM plans also include VoLTE and Wi-Fi Calling, and some include data rollover, all of which we’ll dig into further down in this article.
O2 also offers Data Only plans for tablets, MiFi devices and dongles. These are designed to give you data, without minutes or texts.
They are available on 1, 12 or 24-month contracts with up to unlimited data.
|
|
Mobile Phones |
|---|---|
|
Plans Available |
✔ |
|
Add-ons available |
✔ |
|
Max Data Allowance |
250GB |
|
Add-on expiry |
30 days |
|
Data Rollover |
1 month |
|
Top Up Expiry |
6 months inactivity |
|
Tethering |
✔ |
|
EU Roaming |
✔ |
O2 has a number of Pay As You Go bundles available, giving you an allowance of minutes, texts and data that last for 30 days. They top out at 250GB of data, and they let you roll over up to 1 month of data, giving you extra time to use it.
They also come with tethering and European roaming as standard, and most also come with international minutes that you can use to call over 42 countries from the UK.
|
|
Mobile Phones |
SIM Only |
Data only SIM |
||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
5G |
✔ |
✔ |
✔ |
||||||||||||
|
Roaming |
✔ |
✔ |
✔ |
||||||||||||
|
Tethering |
✔ |
✔ |
✔ |
||||||||||||
|
Wi-Fi Calling |
✔ |
✔ |
✖ |
||||||||||||
|
VoLTE |
✔ |
✔ |
✖ |
||||||||||||
|
Data Rollover |
✔ |
✔ |
✖ |
||||||||||||
|
Spending Caps |
✔ |
✔ |
✔ |
||||||||||||
|
Unlimited Data |
✔ |
✔ |
✔ |
||||||||||||
|
Family Plans |
✔ |
✔ |
✔ |
||||||||||||
|
Credit Check |
✔ |
✔ |
✔ |
||||||||||||
|
eSIMs |
✔ |
✔ |
✔ |
||||||||||||
|
O2 Priority |
✔ |
✔ |
✔ |
O2’s plans come with many perks and additional features, as you can see in the table above. We’ve detailed these in full below.
O2 offers 5G as standard on Pay Monthly, SIM Only, Pay As You Go, and Data Only plans, so you won’t have to pay any extra to get it, and you can get it on a wider range of plan types than some networks.
You can roam (up to a fair usage allowance of 25GB) at no extra cost in the following locations:
Austria, Azores, Belgium, Bulgaria, Canary Islands, Croatia, Cyprus*, Czech Republic, Denmark, Estonia, Finland, France, French Guiana, Germany Gibraltar, Greece, Guadeloupe, Guernsey, Hungary, Iceland, Ireland, Isle of Man, Italy, Jersey, Latvia, Liechtenstein, Lithuania, Luxembourg, Madeira, Malta, Martinique, Mayotte, Monaco, Netherlands, Norway, Poland, Portugal, Reunion, Romania, Saint Barthelemy, Saint Martin, San Marino, Slovakia, Slovenia, Spain, Sweden, Switzerland, and Vatican City.
The vast majority of those also offer 5G roaming (at least, in the parts of those locations where 5G is available).
O2 stands out here as it’s the only major UK network that isn’t currently charging for European roaming on at least some of its plans.
Plus plans also let you roam for free in the following 27 destinations for 75 in total: Argentina, Australia, Botswana, Canada, Chile, Colombia, Costa Rica, Ecuador, El Salvador, Greenland, Guatemala, Guinea, Guyana, Honduras, Madagascar, Mexico, Myanmar, New Zealand, Nicaragua, Panama, Paraguay, Peru, Rwanda, United States, Uruguay, Venezuela and Yemen, with unlimited data, minutes, and texts. Though note that while there’s no limit on data, your speeds will be capped at 2Mbps.
Or if you’re an ultimate Plan customer you can instead roam in the following 75 places (on top of Europe) for 123 worldwide destinations in total:
Albania, Anguilla, Argentina, Aruba, Australia, Bahamas, Bangladesh, Barbados, Belarus, Bermuda, Botswana, Brazil, British Virgin Islands, Canada, Cape Verde, Cayman Islands, Chile, China, Colombia, Costa Rica, Dominica, Dominican Republic, Ecuador, Egypt, El Salvador, Ghana, Greenland, Grenada, Guatemala, Guinea, Guyana, Honduras, Hong Kong, India, Indonesia, Israel, Jamaica, Japan, Kenya, Madagascar, Malaysia, Mexico, Moldova, Montenegro, Montserrat, Myanmar, Netherlands Antilles, New Zealand, Nicaragua, Nigeria, Pakistan, Panama, Paraguay, Peru, Qatar, Rwanda, Saint Kitts and Nevis, Saint Lucia, Saint Vincent and the Grenadines, Saudi Arabia, Singapore, South Africa, Sri Lanka, Suriname, Thailand, Trinidad and Tobago, Turkey, Turks & Caicos, Ukraine, United Arab Emirates, Uruguay, USA, Venezuela, Yemen, and Zambia.
As with Plus plans, you get unlimited texts and minutes in this expanded list of locations, along with unlimited data at 2Mbps.
But if you don’t have one of these plans then you’ll have to pay £7 per day to get unlimited data (at 2Mbps), minutes, and texts in: Albania, Anguilla, Argentina, Aruba, Australia, Bahamas, Bangladesh, Barbados, Belarus, Bermuda, Botswana, Brazil, British Virgin Islands, Canada, Cape Verde, Cayman Islands, Chile, China, Colombia, Costa Rica, Dominica, Dominican Republic, Ecuador, Egypt, El Salvador, Ghana, Greenland, Grenada, Guatemala, Guinea, Guyana, Honduras, Hong Kong, India, Indonesia, Israel, Jamaica, Japan, Kenya, Madagascar, Malaysia, Mexico, Moldova, Montenegro, Montserrat, Myanmar, Netherlands Antilles, New Zealand, Nicaragua, Nigeria, Pakistan, Panama, Paraguay, Peru, Qatar, Rwanda, Saint Kitts and Nevis, Saint Lucia, Saint Vincent and the Grenadines, Saudi Arabia, Singapore, South Africa, Sri Lanka, Suriname, Thailand, Trinidad and Tobago, Turkey, Turks & Caicos, Ukraine, United Arab Emirates, Uruguay, USA, Venezuela, Yemen, and Zambia.
O2 offers tethering as standard on all of its plans, allowing you to use any or all of your data allowance towards it – though the network doesn’t recommend this use and warns that this can use up your data quickly.
Fortunately, O2 also has plans with high data allowances, currently topping out at unlimited, so you can have a lot of data to play with.
However, there is a fair usage policy saying not to use more than 650GB of data per month, and not to tether more than 11 devices.
Wi-Fi Calling means making calls over Wi-Fi with your normal number and calling apps – so you can stay in touch as normal when there’s no signal, as long as you’re connected to Wi-Fi.
O2 offers this at no extra cost on Pay Monthly and SIM Only plans, and it works with all the 4G and 5G devices the network currently stocks.
In the case of some Android devices, your phone will also need to be running O2 firmware for Wi-Fi Calling to work.
VoLTE is also known as Voice Over LTE or 4G Calling, and it means you can call and text using 4G, rather than your phone having to switch to a 2G or 3G signal. This in turn means you can call and text in places that only have a 4G signal, and can potentially get superior call quality.
VoLTE works on the same selection of handsets as Wi-Fi Calling, including all of the 4G and 5G smartphones currently sold by O2.
As with Wi-Fi Calling, you also need to be running O2 firmware if using certain Android devices.
O2 offers data rollover on Pay Monthly and SIM Only plans, but only on its pricier Pay Monthly Plus and UItimate plans. Choose one of these and you'll get one extra month to use your data, assuming you don't have an unlimited allowance.
You can also get data rollover on Pay As You Go, and on these plans it comes as standard.
O2 lets you add a spending cap to your account, of between £0 and £200. That refers to how much you can spend outside of your standard monthly price, for example on premium rate or international calls, or when you’ve used up your allowances. You can also choose not to have a cap if you’d prefer.
O2 offers unlimited data on most plan types other than Pay As You Go, so if you don’t want to worry about using up all your data, you don’t have to. There is however a fair usage policy of 650GB per month, and no more than 11 tethered devices.
O2 lets you add multiple plans to your account, and these can be used by different people. It doesn’t frame this as a ‘family plan’, but you can have up to 20 connections on one account, and you’ll get a 20% discount on the airtime portion of the costs for any extra device or SIM that you add, so it’s cheaper than having multiple O2 accounts.
Like most networks, O2 carries out credit checks. However you can avoid these by opting for a Pay As You Go plan.
O2 offers eSIMs on its pay monthly plans, including both plans that come with a new phone and SIM Only plans, as well as on Pay As You Go. If you’d like an eSIM on a compatible plan, just select one at checkout, or switch to eSIM through the My O2 app or your My O2 account on the web.
All Pay Monthly and SIM Only plans come with access to O2 Priority – so you can grab exclusive offers and early gig tickets. O2’s plans also allow you to automatically connect to many of the network’s Wi-Fi hotspots across the UK. Plus, you can roam across much of Europe at no extra cost – and in some cases even further afield. We’ve got more details on roaming above.
Some plans also chuck in additional freebies. At the time of writing for example, you can get a 6-month subscription to your choice of Disney Plus, Amazon Prime, Amazon Music Unlimited, Audible, McAfee, and others thrown in on select plans.
O2 has won a lot of awards, including being hailed as having the Best Mobile Network Coverage at the Uswitch Telecoms Awards 2026 and in 2025, as well as getting the Best Mobile Network for Roaming award from Uswitch in 2025.
|
Network |
Download/upload speeds |
Loaded latency (ms) |
|---|---|---|
|
EE |
53.2/10.4Mbps |
583.53ms |
|
Three |
51.0/9.3Mbps |
405.93ms |
|
Vodafone |
37.5/7.4Mbps |
449.16ms |
|
O2 |
32.8/6.4Mbps |
1039.19ms |
O2’s average download speed is 32.8Mbps according to Opensignal, while its average upload speed is 6.4Mbps, and its average loaded latency (the time in which it takes for the network to respond to a request) according to Speedtest is 1039.19ms.
Those results aren’t great – as you can see in the table above O2 comes out slower than any major rival, with EE in particular storming ahead at almost double the speed.
Note that these speed results are from January 2026 and combine all available network types (so 5G, 4G and 3G), while the latency is from the second half of 2025. For latency, lower numbers are better, and ‘loaded latency’ specifically means the latency when the connection is under heavy use.
As for 5G on its own, that same January 2026 report from Opensignal found that O2 managed average 5G download speeds of 89.9Mbps. That’s a lot faster than 4G, but slower than rivals in the same test, with Three leading at 187.0Mbps, followed by Vodafone with 130.9Mbps, and then EE with 92.2Mbps.
There’s also a RootMetrics report from the second half of 2025, which found that O2’s median 5G download speed was 111.0Mbps and that its 95th percentile 5G download speed (meaning close to its highest) was 382.4Mbps, again putting it behind Three, EE, and Vodafone in both cases.
Finally, a Speedtest report from 2025 put O2’s median 5G download speed at 78.92Mbps and its median 5G upload speed at 8.28Mbps. All of which were also worse than Three, EE, or Vodafone’s results.
O2’s traffic management policy allows you to use your full data allowance without any restriction in the UK (within fair usage limits), even during peak hours, and once you’ve run out your data service will cease until you purchase more or reach your next month of allowances.
However, the network adds that it will always prioritize emergency voice traffic (which shouldn’t noticeably affect you and is a good thing if you ever need to call emergency services).
O2 will also warn users whose use is excessive enough that it detrimentally affects other customers, and if these excessive users don’t change their usage they risk being disconnected.
When roaming, data speeds may be slower than at home.
|
Frequency |
Frequency Band |
Network |
|---|---|---|
|
700MHz |
n29 |
4G & 5G |
|
800MHz |
Band 20 |
4G |
|
900MHz |
Band 8 |
2G |
|
1400MHz |
Band 32 |
4G |
|
1800MHz |
Band 3 |
2G & 4G |
|
2100MHz |
Band 1 |
4G |
|
2300MHz |
Band 40 |
4G |
|
2600MHz |
Band 41 |
4G |
|
3400MHz |
n78 |
5G |
|
3600MHz |
n77 |
5G |
|
26,000MHz |
n258 |
5G |
|
40,000MHz |
n259 |
5G |
O2 uses the 800MHz, 1400MHz, 1800MHz, 2100MHz, 2300MHz, and 2600MHz bands for 4G. It’s got a decent amount of spectrum and the 800MHz band is well suited to delivering coverage across the UK. It’s long range, so it can travel a long way between base stations, making it suited to rural environments.
But it’s also good at penetrating walls and other solid objects, making it a good fit for towns and cities too, and ensuring strong coverage both indoors and out. The 2600MHz band on the other hand is more suited to busy areas, but it's shorter range and not as good at passing through obstacles. The remaining bands sit in between.
O2 also has some 3400MHz, 3600MHz, 26,000MHz, and 40,000MHz spectrum, which is higher frequency and shorter range than even the 2300MHz band. This is used for 5G. Right at the other end of the scale the network also has some 700MHz spectrum, which is likely to be deployed for both 4G and 5G.
You can find in depth details of these bands and others in our 4G and 5G frequencies guide.
Customer service can be hard to judge, but in a 2025 Ofcom customer service report, O2 was found to have a 85% satisfaction rate from customers, with 14% finding reason to complain, 63% being happy with the way their complaint was handled, and 23 out of every 100,000 subscribers making a complaint to Ofcom. Those numbers are variable, with some being similar to rivals and others being worse.
Then there’s Trustpilot, which based on 21,803 user reviews at the time of writing gives it 1.2 stars out of 5. That’s considered a ‘bad’ rating – though note that many networks are poorly rated there.
O2 combines a sturdy network with high data limits and special offers through O2 Priority. Roaming on O2 is also included, and there are a range of flexible tariffs to choose from whether you Pay Monthly, go SIM Only or Pay As You Go.
O2’s main issue is simply that its speeds don’t appear as high as rivals, but if you have 5G then the available speeds should still be plenty fast enough for most people.
If you want a network with the same coverage as O2 then there are a number of options, including Giffgaff, Sky Mobile, and Tesco Mobile. These all use O2’s infrastructure and spectrum, so their coverage is identical.
They’re typically cheaper too, however they don’t have as many plan types and extras as O2, though they do all offer 5G at least.
Alternatively, you might just want another big-name network, in which case your options are EE, Three or Vodafone. These are arguably O2’s main competitors, since like O2 they have their own infrastructure and spectrum, but that means coverage differs, so it’s worth checking what coverage is like near you on each network before choosing one.