Siemens Mobility Limited has landed a £1.5bn contract to build the next generation of trains for the Piccadilly Line, with Transport for London (TfL) pledging the new fleet of 94 trains will “transform the experience” of millions of passengers.

The much-needed investment will mean the replacement of the entire 1970s Piccadilly line fleet and combined with a signalling upgrade the peak period capacity on the busiest central sections of the line will increase by more than half by the end of the 2020s. This will mean an additional 21,000 customers will be able to board trains every hour during peak times, according to the capital’s transport body.

With more than 700,000 customers using the line on a daily basis and with London’s population set to increase to 10.8 million by 2041, the long-term investment is needed to combat a limited fleet size and old signalling technology which has restricted TfL’s ability to increase capacity across the line for many decades.

While the deal is for 94 trains, TfL says the contract will be awarded on the expectation of a single manufacturer building the trains for all four Deep Tube lines which include the Bakerloo, Central and Waterloo & City Lines.

By the end of 2026, transport bosses expect the additional trains and improved signalling to enable up to 27 trains-per-hour to operate at peak times meaning a train every 135 seconds at the busiest times.

Commenting on the announcement, Mike Brown, commissioner of TfL, said: “Today’s announcement of our intention to award the contract to design and build a new generation Tube train is a huge milestone for London Underground. We are delivering the biggest investment programme in our history to continue to improve customers’ journeys and support London’s population and employment growth. These trains will transform the journeys of millions of our customers, and provide faster, more frequent and more reliable trains for decades to come.”

Siemens have said to be awarded the contract following a “comprehensive and strict procurement process” which evaluated key criteria focused on deliverability, technical expertise and value for money. The contract award is subject to a statutory 10-day standstill period.

Sabrina Soussan, chief executive of Siemens Mobility, added: “We are thrilled by today’s announcement. Our metro trains travel the equivalent of 60 times around the world each week, transporting millions of passengers comfortably and efficiently. With this extensive knowledge and our constant focus on value provision, we can drive down lifecycle costs and significantly improve the passenger experience.”

Furthermore, Tfl has revealed 22 UK suppliers have been identified in the bid to potentially work with Siemens on the build of the trains with at least 50 new apprentice and graduate positions potentially being created.