Under the so-called Central Track Alliance contract, the infrastructure group would be responsible for the development, design and delivery of track renewals and crossings across London North West, London North East and East Midland routes.
Balfour, which has an 80% stake in the 10-year alliance, would also look after the associated infrastructure works.
The company said it expects a full contract award to be confirmed in the second quarter of 2019 and works to begin later this year.
"As one of the UK's leading rail infrastructure suppliers, Balfour Beatty is proud to be part of the alliance appointed to ensure the reliability of the UK's rail network,” said chief executive Leo Quinn.
"We believe that industry collaboration is the way to drive higher efficiency and service standards. Network Rail's new alliance model is a great step forward in rail contract procurement."