Revealed: The best and worst UK cities for mobile signal

Mobile phone

Mobile signal is affected by population density as well as tall buildings CREDIT: GETTY IMAGES

London is among the UK’s worst cities for mobile coverage, with the capital coming 13th in a ranking of the country’s 16 biggest metropolitan areas.

Data from mobile network tester RootMetrics shows that only three cities – Bristol, Hull and Cardiff – fare worse than London in the rankings of cities with populations higher than 500,000.

Belfast was found to have the strongest signal in an average of the UK’s four mobile providers – EE, Vodafone, O2 and Three – despite having a population over 18 times smaller than London. The data, which covers the second half of 2016, showed London slipping from 10th place in the first half of the year.

Big cities often suffer from sub-par mobile networks. It is more difficult to build towers and masts in built-up urban areas, and tall buildings often interfere with radio waves.

Denser populations also mean that more smartphones are trying to latch on to receivers, reducing the strength of each individual signal. However, other major cities including Birmingham and Manchester have significantly better networks.

London had the 13th-best signal
London had the 13th-best signal CREDIT: ALAMY

As well as meaning dropped calls and slower data, poor signal strength also affects battery life, since a smartphone has to work harder to find a connection.

RootMetrics measured mobile networks for reliability, download speed, internet availability, and call and text availability. Earlier this month, it found that the capital also lags in 4G coverage, with one network – Three – covering less than two thirds of London in 4G signal.