Automated signalling improvements on the Metropolitan line between Finchley Road and Preston Road have already cut journey times by one minute, Transport for London (TfL) has confirmed. This is part of the wider £5.5 billion Four Lines Modernisation Project, which also covers the District, Circle, and Hammersmith & City lines.
New Timetable and Service Uplift
Thanks to the signalling revamp, TfL plans to introduce a new timetable in January 2027. By 2028, the Metropolitan line is expected to run 30 trains per hour through central London, up from the current frequency.
Four Lines Modernisation Project Progress
The project began in July 2015 with the rollout of new walkthrough trains featuring CCTV and air conditioning. The focus has now shifted to replacing outdated signalling systems, some dating back to the 1940s, with automated or improved technology.
To date, nine out of 15 signalling projects across the four lines have been completed. According to TfL Programme and Investments Committee agenda papers, the next upgrades will target the Metropolitan line between Preston Road and Moor Park, and sections of the District line between Fulham Broadway and East Putney, and Barons Court and Stamford Brook. These will further reduce journey times.
Delays and Completion Date
The overall project completion has been pushed back from 2027 to 2028 due to the complexity of signalling work on the Metropolitan line north of Moor Park and northwest of West Harrow to Uxbridge. Integrating the new system with the Piccadilly line and Chiltern Railway services, which share the same tracks, has proven challenging.
The entire £5.54 billion scheme is now expected to conclude in 2029, after final software optimisations. This will mark 14 years since the project's inception.
