Ofcom study exposes persistent mobile signal problems across Britain's rail network

Mobile connectivity on Britain's railways remains unreliable for millions of passengers, according to a new study by communications regulator Ofcom, which found that mobile networks frequently fail to deliver the performance needed for everyday online activities during train journeys.

The research, carried out by connectivity mapping specialist Streetwave on behalf of Ofcom, assessed mobile performance across 24 rail routes in England, Scotland and Wales. The findings reveal widespread coverage and capacity issues, with operators failing to meet Ofcom's benchmark for "good performance" in between 58% and 83% of tests.

Ofcom defines good mobile performance as download speeds of at least 5Mbps, upload speeds of 1.5Mbps and latency below 50 milliseconds – sufficient for activities such as video calls, streaming content and browsing social media.

Among the UK's four mobile network operators, EE recorded the strongest results, achieving the benchmark on 42% of route segments tested. Three followed on 21%, while O2 and Vodafone achieved 20% and 17% respectively.

The findings suggest that many passengers continue to experience unreliable mobile service throughout significant portions of their journeys, despite growing expectations for seamless connectivity.

Ofcom said the challenges stem from a combination of weak trackside coverage and the difficulty mobile signals face penetrating some train carriage designs.

The regulator also examined onboard Wi-Fi services provided by train operators, with results highlighting even greater challenges. According to the study, onboard Wi-Fi met Ofcom's performance standard only around 1% of the time.

Outdated equipment, bandwidth limitations and restrictions on network speeds were cited as key reasons for the poor performance.

Performance varied considerably between routes. The corridor between Basingstoke and Coventry was identified as one of the weakest-performing sections of railway, while services between London Victoria and East Croydon delivered some of the strongest connectivity results.

The rail findings form part of Ofcom's wider report, Connectivity You Can Count On, which calls for a coordinated national approach to improving mobile services across the UK.

The regulator highlighted planned investment from network operators, reforms to telecommunications planning rules and emerging technologies such as satellite communications and spectrum-sharing arrangements as potential solutions. However, it acknowledged that improving rail connectivity would require cooperation between government, infrastructure managers, train operators and telecom providers.

Natalie Black, Ofcom's Group Director for Infrastructure and Connectivity, said: "People rightly expect connectivity they can count on."

She added that delivering consistent mobile coverage would require a "joined-up national effort" involving industry, government and local authorities.

Industry representatives have pointed to the unique technical difficulties associated with providing reliable connectivity on moving trains. Mobile UK, which represents the UK's major network operators, said railway environments present "unique structural and capacity challenges" and called for continued investment and supportive policy measures to improve trackside coverage.

The findings come as the government explores options to improve passenger connectivity, including the potential use of low-earth-orbit satellite services, enhanced trackside fibre networks and new technologies designed to overcome signal blackspots in tunnels and remote areas.

With passengers increasingly expecting reliable internet access for work, entertainment and communication while travelling, the report is likely to intensify pressure on both the rail and telecommunications sectors to deliver meaningful improvements in onboard connectivity.