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Which phone network offers the best signal?

By Hamse Yusuf

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Which phone network offers the best signal?

New mobile phone signal analysis, conducted in autumn 2018, has found 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 2018, we've focused on 4G performance. We looked at network performance over a three-month period, from June to August 2018, and found that EE continues to offer average 4G download speeds that are far higher than 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 87% of the time.

The conclusion is clear – if 4G is important to you, 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 2018, EE customers received by far the fastest average 4G speed – 28.9Mbps - though that's slightly slower than the average speed we recorded back in winter (29Mbps). However, 28.9Mbps is still faster than many people will get from their home broadband connection.

Vodafone has overtaken Three as the provider with the second-best 4G speed, improving to 21.92Mbps from 18.9Mbps. Three's speed slipped down from 22.3Mbps to 18.78Mbps.

O2's average speed also dipped slightly - from 15.1Mbps to 14.61Mbps.

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 continue to considerably improve how often their customers can access a 4G signal.

EE customers still have the best chance of getting a 4G signal and on average can access it 86.8% of the time (up from 78.5%).

O2 and Vodafone customers may not enjoy quite the same level of access to a 4G signal (available on average 83.2% and 80.3% of the time) but they have both made gains on EE - availability is clearly getting better.

Three is by far the most improved network, gaining a16.1% increase in average availability from 57.1% to 73.2% in just six months.

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 25.92Mbps.

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

Vodafone had the largest gain of 4.2Mbps with O2 and Three gaining 0.9 and 1.2Mbps in their combined speed respectively.

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

Three is the front runner here with speeds of 7.82Mbps - although EE is not far behind, also breaching the 7Mbps mark.

O2 and Vodafone lag quite far behind here, acheiving the same 3G speed (4.58Mbps).

How OpenSignal collects signal data

The information in this report is based on more than 1.1bn data readings taken from people who have downloaded the free OpenSignal app. In total, OpenSignal tracked 76,939 UK app users around the clock from 1 June to 29 August 2018, 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 – the proportion of time 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.