The new stretch of A595 between Parton and Lillyhall, connecting West Cumbria and the towns of Whitehaven and Workington with the M6 motorway at Penrith via the A66, is due to reopen fully before Christmas, the Highways Agency said in a progress report.
The work began in January 2007 to create a new A596 junction at Lillyhall and build a new bypass to the west, around the villages of Distington, Common End and Howgate before rejoining the A595 north of Parton.
The Highways Agency said all the main bridges are now complete with the exception of Distington Overbridge which will be completed in late November/early December 2008.
Road surfacing is approximately 85% laid and the remainder scheduled to be laid and finished by late November.
The wet summer slowed progress and the road completion date was put back.
A statement from the agency said: "Over the next few months we hope to complete all the carriageway works. It is planned to open the road before Christmas 2008 – subject to weather conditions."