Transport Scotland has published the tender notice for the £5M A737 Den Realignment project.
The job involves upgrading 1km of road and constructing new junctions between Beith and Dalry.
The notice follows the £31.2M contract to construct the A737 Dalry Bypass to a Farrans Roadbridge joint venture last month.
Scotland’s minister for transport Humza Yousaf said: “This highlights the significant progress we are making towards improving the A737 for the North Ayrshire communities. The investment in improving the A737 will deliver upon completion, a number of benefits for the local North Ayrshire communities as well as road users travelling longer distances.”
Shortlisting will take place this summer with the contract award expected next spring.