The new contract has been signed with Bombardier Transportation and also covers the provision of maintenance and support services.
The arrangement is expected to run for the duration of the West Midlands Trains franchise and builds upon an announcement previously made in October, which saw Bombardier named as the preferred bidder for the deal.
Corelink Rail Infrastructure, which is co-owned by Deutsche Asset Management and Infracapital, is set to lease the new fleets to West Midlands Trains under the agreement.
West Midlands Trains is a joint venture (JV) company comprising Abellio UK, the East Japan Railway Company (JR East) and Mitsui & Co.
The JV secured the West Midlands franchise from the Department for Transport in August and began operations earlier this week.
Abellio UK managing director Dominic Booth said: “This is all part of the £1bn investment we’re bringing to the West Midlands franchise.
“Customers will enjoy new trains and upgraded stations, along with a whole host of other benefits.”
Bombardier has agreed to produce and maintain 333 electric carriages under the arrangement.
The contracted vehicles will feature 36 three-car trains for metro services and 45 five-car trains for outer suburban operations.
The three-car trains are capable of running at 90mph, while the five-car variants will be able to reach top speeds of 110mph.
Bombardier’s AVENTRA vehicles have previously been ordered for Transport for London’s Elizabeth line (Crossrail) and London Overground’s LOTrain, as well as the South Western Railway and Greater Anglia franchises.
The company is scheduled to begin the delivery of the new vehicles in 2020 and complete the hand-over process by 2022.