The £70.5m job to upgrade the M6 between J10a and J13 to a smart motorway with all lane running has been brought forward from a planned start in the first quarter of 2014.
The project will cost in total around £87.5m, significantly below the Government cost estimate of £140-£200m at the time of the spending review.
Carillion will increase motorway capacity by converting the existing hard shoulder between 11a and 13 to an additional permanent running lane with smart motorways technology.
Advanced enabling works started in September and full construction can now continue after the contract was signed off today.
The full scheme is expected to be completed by spring 2015
Carillion is already successfully delivering a smart motorway project for the Highways Agency between Junctions 5 and 8 on the M6.
Roads Minister Robert Goodwill said: “This is yet another example of work starting sooner than planned, which is great news for road users and local businesses.”