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Mobile phone coverage across the UK

Mobile phone coverage in London

By Jon Barrow

Article 2 of 13

New data from Which? and Opensignal uncovers the reality of 4G coverage throughout the UK. Find out what it's really like in London and see which provider has the best 4G network.

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The information contained on the page is based on mobile phone coverage from June to August 2016. You can read more up to date analysis in our 2017 national report and 2017 city breakdown.

New research by Which? and OpenSignal has found that London has the best 4G availability in the UK, with mobile phone users able to access the fast network almost 70% (69.7%) of the time.

Meanwhile, Wales came bottom of our availability rankings. Customers there could only get a 4G signal 35.4% of the time – that's 10 percentage points lower  than the next-worst region (the South West – 45.7%).

Ultimately, if you need a 4G signal in London, then there's a good chance you'll get it.

Find out which network is the best where you live with our free coverage checker.

Although 4G availability is very good, London's average 4G speed is, surprisingly, the worst of any region we tested.

Our results show that phone users in the city have an average download speed of 18.8Mbps. At the other end of the table, Northern Ireland boasts the top average download speed of 23.3Mbps. Yorkshire and Humberside, and the East Midlands are close behind with speeds of 22.8Mbps each.

The reason for these low speeds is that the capital's huge population and demand for mobile data means more people are connecting to 4G there than anywhere else in the country. That, in turn, creates congestion on the network, dragging down speeds for everyone.

Best network for 4G availability in London

From looking at the four phone networks in London, we found that EE customers have the best chance of getting a 4G signal (available 79.2% of the time).

The worst performer in the region is Three, which offers just 59% 4G availability.

3G availability and speeds in London

If 4G isn't available, customers will often drop on to the slower 3G network.

According to our research, customers in London can access 3G or 4G 91.6% of the time, which, again, is better than any other region that we looked at. Yorkshire and Humberside was in second place in our rankings, though at 86.7%, its availability was almost 5% lower.

Our analysis

The information used in this analysis comes from a regular collaboration between Which? and coverage experts OpenSignal, and is based on more than 500m data readings taken from people that have downloaded the free OpenSignal app.

By tracking 28,841 UK app users around the clock between June and August 2016, we're able to give a definitive account of the real mobile phone user experience. We're able to accurately report on network speeds and to chart our own metric, ‘availability', which looks at the proportion of time that users have a network connection.

We think that this unique availability measurement, which determines whether the network is doing its job by providing a connection where it's needed most, is far more valuable than simply reporting predicted coverage based on computer models or one-off drive-by tests.

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

Which network do you say is best?

Once you know which networks offer the best coverage where you live and work, you'll want to know which ones offer the best customer service and value for money. We asked 4,100 members of the public to tell us about what they love and hate about their network.

Read the results of our best mobile networks survey to find out the winners and the losers.