OpenSignal UK State of the Market Report

in association with


In this report we look at the current state of mobile network provision in the United Kingdom. We have teamed up with Which? the UK’s leading consumer group, to produce a report that will help consumers better understand the difference between mobile networks. Our data shows which networks provide the fastest 4G and 3G speeds and who has the best coverage.

As you can see on the right, Vodafone and EE split the 4G honours; EE has the best coverage while Vodafone users enjoy the best speed. Perhaps more surprising is that average 4G speeds are falling – more on that below. On 3G 3 users spend the most time with a connection to the 3G network.

To understand which network provider offers the best coverage we use a measurement called ‘time on network’ (*). This metric is based on data shared with us by our users - we check the type of network connection they have every 15mins in order to determine the proportion of time they spend on 2G, 3G, 4G and with no network connection at all. While current coverage maps are based on computer models that predict coverage, they don’t take into account whether you are indoors or outdoors, trees and buildings that might be blocking your signal or the load on the network. Our time on metric does, because it’s based on real data from real users. Incorporating 68 million data readings from 40,000 users our maps offer a real reflection of the coverage – good and bad – you can expect day-to-day.

This state of the nation report covers the UK as a whole but we’ll be following it up with regional reports looking at the best and worst networks where you live in the coming weeks.

Map of 3G coverage

This map shows the proportion of time users across all networks have access to a 3G connection, using the ‘Time on’ metric explained in the introduction. This map shows the proportion of time the average user on a 3G (i.e. not 4G) plan has access to the network, with the remainder being the time they have either on 2G or with no signal at all. While 3 are the clear winners – it’s worth remembering that they have no 2G network – meaning that if a user has no 3G or 4G connection then they will be unable to make calls or texts. Users on other networks will still be able to make calls and send texts by using their network’s 2G connection.

Perhaps unsurprisingly, 3G coverage is best overall in London, with the south east and west midlands also comparatively well served. 3 perform best for 3G coverage, with both 3 and EE performing comparatively better in regions outside of London.

Click on the tabs to see 3G coverage for each network individually.

Map of 4G LTE Coverage

Just like 3G, London has the best overall 4G LTE coverage, with users having access to the network over 50% of the time. The extent to which 3 remain reliant on 3G is revealed by the difference in the two maps, with 3 entirely green for 3G coverage but almost entirely red for 4G LTE.

Despite EE users enjoying more time on 4G LTE than users on other networks (see chart below), this does not manifest as any specific regional superiority. The maps for EE, O2 and Vodafone show no particular strong geographic bias, although we’ll be digging into this in greater detail on a city-by-city level in our regional reports.

Overall Time on Combined 3G/4G Last 3 Months

This metric looks at the combined proportion of time that users spend on networks that are 3G or better. As 4G LTE becomes more widespread this is an important metric for judging the overall coverage of networks.

3 have the highest time on combined 3G/4G LTE networks, although as we’ve seen in the maps above that’s thanks to their 3G network rather than 4G. 3 also lacks a 2G network so there is no back up for making calls or sending texts. The best network that also has 2G was EE, with its users having access to 3G or 4G LTE 81% of the time over the past three months.

At times EE, O2 and Vodafone will move customers on to 2G during voice calls, even though 3G and 4G coverage is available, in order to prioritise data traffic on the faster networks. However, Ofcom figures show that the time spent on voice calls is incredibly low, and is falling, and so the impact on the figures we've quoted is likely to be minimal (OfCom figures show that users spend approximately 0.4% of the time making calls).

Time on 4G LTE Last 3 Months

Obviously if you’ve paid for a 4G connection and the faster speed it offers, you won’t be especially happy if you can only get 3G. Here you can see how far behind 3 is in 4G coverage – it was after all the last network to launch its 4G network. The first network to launch was EE and it shows. EE is comfortably ahead of its rivals for overall 4G LTE coverage.

Vodafone and O2 perform similarly, with Vodafone just climbing ahead of its rivals into second place. 4G coverage is growing and with that comes a corresponding increase in users. As you’ll see in our graph below, more users generally means slower speeds – as increased load slows down the network.

Time with no signal Last 3 Months

For any mobile phone user, time spent with no signal at all is the worst case scenario (unless there is Wi-Fi handy). While not having access to 3G or 4G is frustrating, having no signal whatsoever means that their device cannot even send texts or make calls - the most basic mobile functionality. The proportion of time that users cannot access the mobile network at all is therefore an extremely important measure of a network's overall coverage, rather than simply their data coverage.

Users on 3, which has no fallback 2G network, spend the most time without access to any mobile network - with the average 3 user spending almost 14% more time without a connection than the average Vodafone user.

Average 4G LTE Speed Last 3 Months

Vodafone has the fastest 4G LTE in the United Kingdom as measured over the past three months – with 3 some way behind the other networks.

To put these speeds into context, we recorded the world’s fastest country for 4G LTE as Australia, who averaged 24.5Mbps back in February. However, as noted above, networks tend to get slower as subscriber numbers rise.

However, there is better news back in the UK. When compared with broadband – 4G is faster - with the average ADSL home broadband connection clocking in at 7.4Mbps.

Average 3G Speed Last 3 Months

This graph shows the extent of the difference between 4G LTE and 3G, with Vodafone’s 4G LTE network over three times faster than its 3G network - making a clear difference to consumers.

EE perform well for 3G speed, with 3 performing best - 3's 3G network is only half the speed of its (admittedly comparatively slow) 4G network. O2 perform disappointingly, as the only network to average below 3Mbps.

4G LTE speed over time

As more people sign up to 4G LTE and use the network, the average speed inevitably comes down. The average speed on 4G LTE has nearly halved over the past year in the UK. There are several competing forces at play here - an increase in users slows the network down but the networks are constantly rolling out improvements and adding LTE-enabled cell towers, which goes some way towards explaining the deviations in the downwards line.

3G speed over time

Over the past few months 3G speed has flattened, with no noticeable degradation or improvement to the speeds that users experience.


All of the OpenSignal data is based on information shared with us by OpenSignal users - with almost 40,000 active UK users this allows us to comprehensively survey network performance across the country - with data on speed and coverage being collected automatically 24/7. We believe our data is more representative of the true state of networks than existing testing methods, as we measure the network everywhere people actually spend time (including inside their homes and office) rather than modelling coverage based on drive-test readings which can be performed at peak times for network speeds and with only the highest-end devices.

For coverage we use our 'time on network' metric, which looks at how coverage is experienced by real world users. The OpenSignal app checks the type of connection each user has every 15 minutes, a totally automated process that does not require the user to provide any active input beyond enabiling the feature. This allows us to see how networks actually work for their subscribers, as our data is collected from areas where real users spend their time. Over the last quarter we have collected tens of millions of signal readings, allowing us to accurately measure the proportion of time that users have access to 2G, 3G, 4G or no signal at all.

Our data on network speeds is collected from speedtests run by OpenSignal users, who use the app to check the quality of their connection. The app also runs speedtests in the background, in order to make the data more representative of all times and areas.

(*) Editor’s note: In June of 2016, OpenSignal changed the name of its "time on" metric to network availability. Availability measures the same thing as time on — the proportion of time users remain connected to a particular network — but we felt that "availability" was a better reflection of the metric’s definition. For more details see our methodology page.