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1 October 2020

Which phone network offers the best signal?

New mobile phone signal analysis has found one network is way out ahead when it comes to offering the best 4G service.
Mobile phone network report 439291
Hamse Yusuf

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

In the latest research, published in August 2019, we've focused on 4G performance. RootMetrics looked at network performance over the first half of 2019 and found that EE continues to offer its customers the best network speeds and reliability across the UK, winning the RootScore Award in all but one category and also scooping the overall prize. 

RootMetrics uses its expert algorithms to convert almost 600,000 measurements into easy-to-understand RootScores – marked out of 100.

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 provider reviews.

Overall performance

Overall, EE won out with an almost perfect RootScore of 96.1, winning 44 out of the 96 regional RootScore awards available outright and tying another 46.

Vodafone was not far behind, with a score of 95.2, and was also able to scoop 50 RootScore awards, although all but six were a tied award.

Although Three and O2 scored in the 90s overall, they were slightly left behind, scoring 92.1 and 90.5, respectively.

Network speed

EE won out here with a RootScore of 93.1 and an impressive average UK-wide download speed of 37.6Mbps, comparable with many fibre broadband packages.

Vodafone came close with a RootScore of 91.9, although its average UK-wide download speed could not match EE, clocking a speed of 21.7Mbps.

Three and O2 were significantly behind here, with RootScores of 81.9 and 78.5, respectively. Similarly, the average speeds recorded were low in comparison with EE and Vodafone.

Network reliability

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

RootMetrics network reliability testing provides a look at operator reliability across calls, texts and data and is measured with a variety of real-world-use cases such as downloading/uploading files and assessing call maintenance.

Although all four providers scored well, EE still takes the win with a RootScore of 97.5. Vodafone was second with a score of 96.8 with Three and O2 not far behind.

How RootMetrics collects signal data

The information used in this analysis comes from a regular collaboration between Which? and coverage experts RootMetrics, and is based on just under 600,000 measurements taken from over 19,000 miles of driving, along with testing of 648 indoor locations. 

Using these measurements, we're able to give a definitive account of the real mobile phone user experience using RootScores. 

A RootScore is a simple way to translate all the data gathered into clear and easy-to-understand marks of performance and is scaled from 0-100. The higher the score, the better. 

Read more about the approach, and download the free app, on the RootMetrics website.

How you can help

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

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

To ensure that our reports and the interactive map are accurate, we require as much data as possible. To help provide this, download RootMetrics for free on Android or iPhone.