Transport for London (TfL) and telecommunications partner Boldyn Networks have confirmed that the rollout of 4G and 5G connectivity across the London Underground remains on course for completion by the end of 2026, with several additional stations and tunnel sections now brought online.
The latest phase of the project has expanded mobile coverage across key sections of the Bakerloo, Metropolitan, Circle and District lines, allowing passengers to remain connected for a greater proportion of their journeys.
According to TfL, around 60% of underground stations across the network now have mobile coverage, while work continues at pace to extend connectivity throughout the capital's transport system.
Recent upgrades have introduced coverage in tunnel sections of the Bakerloo line between Queen’s Park and Edgware Road, as well as parts of the Metropolitan line between Euston Square and King’s Cross St Pancras and between Barbican and Moorgate. Additional coverage has also gone live on the Circle and District lines between Cannon Street and Monument, Sloane Square and Victoria, and Bayswater and Paddington.
Several busy stations, including Vauxhall, Temple, Nine Elms and Gloucester Road, have also joined the network. Larger transport hubs such as King’s Cross St Pancras, Victoria and Paddington are being connected in phases due to the complexity of their infrastructure, with initial works focusing on platforms and ticket halls.
TfL expects the majority of the Northern, Bakerloo and Metropolitan lines to have full tunnel coverage by the end of summer 2026.
The programme forms part of a wider £20-year concession agreement awarded to Boldyn Networks in 2021. The neutral-host network enables mobile operators including EE, VodafoneThree and Virgin Media O2 to provide services through shared infrastructure across the Underground, Elizabeth line, Docklands Light Railway and parts of the London Overground network.
Beyond improving passenger connectivity, the network will also support the UK's Emergency Services Network (ESN), providing police, fire and ambulance services with access to critical communications and real-time operational data throughout the Underground system.
Rebecca Bissell, TfL’s Director of IT, said: “Providing mobile coverage across our network means customers can stay better connected while they travel, allowing them to stay in contact with friends and family, shop online and keep up with the latest news and sports results.
“We remain focused on having 4G and 5G mobile coverage across the whole Tube network by the end of the year, and more than 600 engineers work hard overnight during limited engineering hours to help deliver this.”
Deputy Mayor for Transport Seb Dance described the project as a key element of London’s digital infrastructure ambitions.
“It’s brilliant to see this continued progress on the Mayor’s promise of delivering 4G and 5G across the London Underground,” he said.
“In an increasingly digital world, we’re committed to ensuring that all Londoners and visitors have the connections they need – even whilst on the move.”
Alongside the Tube rollout, TfL and Boldyn are also extending coverage to underground sections of the Docklands Light Railway and the Windrush line between Highbury & Islington and New Cross.
The partnership is also deploying small-cell technology on TfL assets such as lighting columns to improve mobile performance in busy urban locations. Areas including King’s Cross, Waterloo, London Bridge, Old Street, The Shard and Hyde Park Corner have already benefited from the upgrades.
The project was originally expected to be completed by the end of 2024, but engineering challenges on some near-surface sections of the network have extended the delivery programme. Despite the delays, TfL says the scheme remains firmly on track to achieve full network coverage before the end of 2026.
