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Which phone network offers the best signal?

By Jon Barrow

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Which phone network offers the best signal?

New mobile phone signal analysis, conducted in autumn 2017, has found that one network is way out ahead when it comes to offering the best 4G service.

We regularly work with independent mobile phone benchmarking experts OpenSignal to report on the state of mobile phone networks in the UK.

In our latest research, published in autumn 2017, we've focused on 4G performance. We looked at network performance over a three month period, from June to August 2017, and found that EE continues to offer average 4G download speeds that are far in excess of those available from rival networks. And while all four networks have improved the availability of their 4G networks, EE customers still have the best chance of getting a 4G signal and are able to access 4G 78% of the time.

The conclusion is clear – if 4G is important to you, then EE is your best bet.

However, speed and network availability shouldn't be your only consideration when choosing a provider – customer service and value for money can be just as important.

See how EE customers rated the network in our latest mobile phone satisfaction survey.

4G speeds


New OpenSignal data revealed that from June through August 2017 EE customers received by far the fastest average 4G speed – 29Mbps, though that's a little slower than the average speed we recorded back in winter (31.8Mbps). However, 29Mbps is still faster than many people will get from their home broadband connection.

Three continues to offer the second fastest average speed - 22.3Mbps which is fairly consistent with its performance in spring - 23Mbps.

O2's average speed was also consistent - staying around 15Mbps - as was that of Vodafone, which was just under 19Mbps.

4G availability


But speed is only part of the story – after all, a superfast service is of little use if you can never get a signal.

The good news is that finding a 4G signal in the UK is easier than it was six months ago.

Our analysis of 4G availability – which tracks the percentage of time a smartphone user can connect to a particular network (rather than simply measuring geographic coverage) – revealed that all four networks have considerably improved their performance since spring.

EE customers still have the best chance of getting a 4G signal and on average can access it 78.5% of the time (up from 72.4%).

O2 and Vodafone customers may not enjoy quite the same level of access to a 4G signal (available on average 74.1% and 71.4% of the time) but they have both made gains on EE - availability is clearly getting better.

The same is also true for customers with Three though the network still offers far worse 4G availability (57.1%) than the other providers.

3G and 4G speeds


The graphic above shows the average download speeds if people use both 3G and 4G networks, switching between them as the 4G signal drops in and out.

Once again, EE is way ahead of the three other providers, with its customers able to get an average download speed of 23.1Mbps.

The other networks are some way behind, and though all have improved their speeds, their gains have been far more modest.


The only area where EE wasn't the sole champion was in our analysis of 3G-only speeds.

Here download speeds from EE and Three are very similar - with customers able to get average download speeds slightly over 6Mbps. Three was the front-runner back in our spring analysis where its average speed was 6.5Mbps.


The information in this report is based on more than 800m data readings taken from people that have downloaded the free OpenSignal app. In total, OpenSignal tracked 51,944 UK app users around the clock from 1 June to 31 August 2017, checking every 15 minutes whether they had a signal.

It then analysed this data to calculate download speeds and network availability.

We think that reporting on availability – that is, the proportion of time that users actually have access to a particular type of signal – is far more useful than simply stating geographical coverage, which is normally based on computer estimates or one-off drive-by assessments. After all, this shows whether users can get a signal where they need it and is therefore a more accurate reflection of the real-life experience.

How you can help

As well as using data from its app to produce these reports, OpenSignal also uses it to generate a free online coverage checker. You can use this to determine the best network for where you live.

To ensure that our reports and the interactive map are accurate, we require as much data as possible. To help provide this, we need you to download OpenSignal's free Android or iPhone app.

The data collected is stripped of any identifying information and uploaded to OpenSignal's servers, taking care to use as little processing power and battery life as possible.

You can read more about the apps and the coverage map on OpenSignal's website.