5G on the Tube – Science Fiction Turned Reality
Have you noticed recently that on parts of the London Underground, you are now able to scroll using data or take/make a phone call, even when you’re going through a tunnel? Just smooth, uninterrupted connectivity. How is that possible?
The step forward for connectivity on the Tube is thanks to London Underground’s Telecommunication Commercialisation Project (TCP). Due to this project, 5G is no longer just above ground — it’s making its way through the network of tube tunnels which stretch out under London’s streets, altering the daily experience for millions of passengers. But which parts of the Tube are connected, and what kind of infrastructure makes this initiative possible?
Where can you get 5G on the Underground in 2025?
As of mid-2025, 4G and 5G coverage is live across some key parts of the London Underground, including:
- Central Line – between Shepherd’s Bush and Bank
- Northern Line – between Hampstead branch, Highgate branch and Embankment / Bank, and Stockwell and South Wimbledon
- Jubilee Line – between Westminster and Canning Town
- Victoria Line – between Vauxhall and Pimlico, and Green Park and King’s Cross & St. Pancras
- Piccadilly Line – between Hyde Park Corner and King’s Cross & St. Pancras
You can view the latest 5G coverage map on TfL’s website here.
Mobile coverage on the London Underground continues to grow, bringing better connectivity to more passengers. Through the latest upgrades, the Northern line’s tunnelled stretch between Balham and South Wimbledon is now fully covered, with stations like Kennington, Oval, Tooting Broadway, and South Wimbledon all coming online. On the Victoria line, coverage has been rolled out between Vauxhall and Pimlico, making it even easier for commuters to stay connected.
These improvements build on earlier expansions, including extended coverage on the Piccadilly and Victoria lines reaching King’s Cross St Pancras earlier this year. Meanwhile, the Elizabeth line has been leading the way, offering full 4G coverage since last year, allowing hundreds of thousands of travellers to browse, stream, and stay in touch while riding London’s newest and most high-tech rail line. London Underground’s goal is to bring 5G to all 272 stations and 400km of tunnels by the end of 2026.
Over 260 stations and counting in TFL’s network (overground and underground) are already connected.
How do you get phone signal on the Tube?
Delivering 5G in a subterranean environment is a challenging task and there are three pieces of technology which play a critical role in delivering the bars to your phone:
- Small cells: These compact, low power cellular radio units are installed throughout stations and tunnels to provide dense, high-speed coverage.
- Fibre backbone: High-capacity fibre optic cables run throughout the network, that carries data between underground equipment and the wider internet. This fibre infrastructure ensures ultra-low latency and high bandwidth, which is essential for 5G performance.
- Centralised antenna systems: These connect to mobile operators’ core networks, ensuring seamless service.
The role of fibre optic cable in making 5G work underground
Behind every 5G signal is a powerful fibre optic backbone which:
- Connect small cells and antennas to the wider mobile network.
- Delivers low-latency, high-bandwidth backhaul, essential for 5G performance.
- Enables real-time data transmission, even in the most complex underground environments.
- Meets strict safety specifications. These cables must be LSZH (Low Smoke Zero Halogen), meaning they are constructed to emit minimal smoke and no toxic halogen gases in the event of a fire, making them ideal for enclosed public spaces, which is a crucial factor in passenger safety.
Why 5G on the Underground matters
Bringing mobile connectivity to the Tube
The goal is to make it easier for passengers to stay connected with friends, family, and work while travelling on the London Underground.
Expanding coverage across the city
With 5 million passenger journeys completed on the London Underground each day, at any given time there are thousands of people on the Tube, so there is an obvious requirement to match above ground connectivity and speed. To boost mobile performance in high-demand areas, the project involves installing 3,400 small cells on existing TfL roadside infrastructure, such as lighting columns. These will enhance 4G and 5G coverage and speeds across London’s dense urban landscape.
Connecting London’s boroughs
In partnership with the GLA and Boldyn Networks, Transport for London is rolling out new gigabit fibre connections to key public sites and CCTV locations across the city. This initiative will support access to education and employment opportunities, helping to drive productivity.
Fujikura’s Role in the Connected City
As London’s Underground embraces 5G and fibre connectivity, the wider rail industry is undergoing a parallel transformation. Across Europe, rail and mass transit networks are evolving into high-speed digital networks and at the heart of this shift is fibre optic infrastructure.
Our Spider Web Ribbon® (SWR®) cable and 90R ribbon splicing technology help to accelerate fibre deployment across rail and transit networks. Unlike traditional loose tube cables, SWR® allows for mass fusion splicing of up to 12 fibres at once, significantly increasing productivity, which is especially beneficial during the limited working windows typical of railway environments.
Our cables also gel-free, which means faster fibre access and preparation, further reducing installation time. This is particularly valuable in high-traffic systems like the London Underground, where minimising disruption is crucial. The combination of SWR® and Wrapping Tube Cable enables rapid, high-density fibre installation that supports the growing demand for bandwidth, reliability, and real-time connectivity across the modernising rail infrastructure.
Final Thoughts: 5G, Fibre, and the Future of Urban Mobility
5G on the Tube isn’t just a technical upgrade; phone signal on London Underground is transforming the way Londoners travel, work, and stay connected. What used to be a signal dead zone is now a place where you can keep streaming, scrolling, and communicating without interruption.
This level of connectivity is the result of collaboration between Transport for London and mobile network operators like EE, Vodafone, Three, and Virgin Media O2. Rather than relying on a single provider, this shared infrastructure model ensures that passengers across all major networks benefit from consistent, high-quality service. It’s a powerful example of how industry-wide collaboration can deliver real value to the public, making digital access more inclusive and reliable for millions of commuters.
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