The project involves constructing just over two miles of new road to provide alternating overtaking facilities in both directions.
The A75 is the trunk road that runs east-west between Gretna, north of Carlisle, and the port of Stranraer.
Transport Scotland has shortlisted the following contractors:
- McLaughlin & Harvey
- Balfour Beatty Civil Engineering
- John Paul Construction
- I&H Brown
- RJ McLeod (Contractors).
Construction is expected to start in 2013 and be completed in 2014.
Transport minister Keith Brown said: “The Scottish government has been clear in its commitment to improving the A75 and we welcome this keen interest from the construction industry. It is through projects such as this that we can support employment opportunities during the construction phase while providing benefits for road users.
“Together with A75 Dunragit Bypass and A77 Symington to Bogend Toll schemes announced in July, we can clearly demonstrate our very real efforts to improve connectivity and make Scotland an attractive option for business, leisure and tourism.
“Upon completion, the scheme will benefit users by improving the performance and safety on this stretch of road, increase the number of overtaking opportunities and provide better facilities for the needs of cyclists and pedestrians."