The £61m scheme will reintroduce passenger train services to Moseley, Kings Heath and Hazelwell for the first time in 80 years.
Design work has started and work on site will begin from November with the stations expected to be completed next autumn.
Malcolm Holmes, director of rail with TfWM, said: “This is a major milestone towards seeing passenger trains restored on the Camp Hill line, with the contractor in place and construction crews gearing up to get on site.
“This means, that after several years of planning and development, we are now entering the final phase and it will not be too long before these stations are complete and open to the travelling public.”
Mike Evans, operations director for VolkerFitzpatrick, said: “Our team are excited to be part of these ambitious plans to create an improved transport network, that will support the region’s ambition to be net zero carbon by 2041.”