The deal worth almost £20m will deliver upgrades at Romford and Ilford stations including improved entrances and step free access.
Ilford station will benefit from a new station building, replacing the existing entrance on Cranbrook Road.
At Romford work will include construction of a new entrance onto The Battis walkway and a better ticket hall, providing improved passenger circulation from the entrance to the platforms.
Main construction works at Ilford are due to start by the end of this year and complete by the end of 2020. The construction programme for Romford will be finalised later this autumn.
Colin Prime, Network Rail’s Principal Programme Sponsor said: “This contract award to VolkerFitzpatrick will enable us to forge ahead and complete the long-awaited upgrades at these two stations.
“This work will deliver significant benefits, providing a better overall journey experience for passengers. This represents the final hurdle to deliver the Crossrail eastern stations programme and a significant milestone for our contribution to this huge project.”
Howard Smith, TfL Rail Director of Operations, said: “Both Ilford and Romford are busy stations on the TfL Rail route and it is great news Network Rail has awarded the contract which will see vital improvement work get underway at both stations.
“Once completed the stations will see new lifts and improved ticket halls, helping Londoners make easier and more accessible journeys. This is another positive step in the preparation for the Elizabeth line.”
Mike Evans, VolkerFitzpatrick project director, said: “After carrying out the preliminary works at Ilford and Romford stations, we are delighted to have been awarded the contract for the main construction phase.
“We look forward to working with our client, in delivering these station upgrades.”