Thirty new trains will be required for West Anglia services from Liverpool Street to Enfield Town, Cheshunt, and Chingford, which will be transferred to London Overground from the Greater Anglia franchise in May 2015. One set will be used on the Romford – Upminster line and the remaining eight units will be allocated to the Gospel Oak – Barking line, which will be electrified by 2017. The acquisition of these trains will allow the redeployment of the eight two-car class 172 DMUs currently employed on this route.

Delivery of the new EMUs will commence in 2017 and the final sets will enter service on the West Anglia routes by 2018.

The contract will include options for additional trains.

London Overground currently operates a fleet of 57 four-car Bombardier class 378 EMUs, which will be lengthened to five cars by the end of next year.