4G Mobile Goes Live on First Tunnel Sections of the Elizabeth Line in London

The latest update from Transport for London (TfL) has revealed that 4G and 5G mobile (mobile broadband) signals have now been extended to cover the first tunnel sections on the Elizabeth line (running approximately 5 miles). Further tunnelled sections to Whitechapel, Canary Wharf and Woolwich will be connected this summer.

Just to recap. Boldyn Networks (formerly BAI), using kit from Nokia and others, currently holds a 20-year concession deal with TfL, which was signed in June 2021 (here) and allows them to build the new 4G and 5G “Ready” (mobile broadband) infrastructure across the whole Tube (London Underground), DLR and Elizabeth line network.

This new network can then be made available via wholesale for Mobile Network Operators (MNO) to harness. The goal of this is to cover the entire London Underground by the end of 2024 (ticket halls, platforms and tunnels), as well as Highbury and Islington and New Cross on the London Overground network.

In terms of the Elizabeth line, all of its stations have already been enabled, and they’ve now started to introduce coverage within the tunnels themselves – starting with the 5-mile section that runs from the Royal Oak portal to the west of Paddington to Liverpool Street station. Further tunnelled sections of the Elizabeth line, towards Whitechapel, will be connected in the coming weeks – the whole line should be done by the end of this summer.

The service also continues to be introduced across the Tube network in Central London, with the Hyde Park Corner and Russell Square stations on the Piccadilly line now receiving coverage. Further sections of the Northern line, Bakerloo line, Piccadilly line and Victoria line are also anticipated to go live in the “coming month“.

As well as all eight ‘underground’ Elizabeth line stations, across London, 36 Tube stations have started to offer mobile coverage to customers in the ticket halls, platform areas and interchanges, with many more, including the southern end of the Northern line, expected to go live by the end of the summer.

London’s Transport Commissioner, Andy Lord, said:

“It’s wonderful to see our programme to introduce high-speed mobile coverage now benefitting customers on the Elizabeth line, the newest part of London’s historic underground network of stations and tunnels.

This key step in bringing better connectivity to London’s underground stations and tunnels will allow more people travelling around the capital to keep in touch, share photos and make the most of the city, especially as we start to enjoy the summer.”

Around 500 people are currently working overnight across the Tube network to install the new mobile equipment, with all works needed to be tidied away before the network opens for customers every morning. Once fully delivered, more than 2,000km of fibre optic cabling, as well as thousands of radios (base stations, small cells etc.), are expected to be installed within tunnels and stations – fitted outside of operational hours.

Overall, nearly 70% of all stations on the Tube network have now started to get mobile coverage, and the project appears to be making good progress. But it should be noted that the original goal of completing everything by the end of 2024 is no longer sound. As the Mayor of London, Sadiq Khan, acknowledged in March 2024: “Small sections of some lines, such as those that are closer to the surface, where partial mobile coverage exists, require bespoke works that may extend into 2025/26.”