The A264 is scheduled to fully re-open on Sunday (June 9).
All lanes on the busy dual carriageway to the west of Bewbush should be back in use following around seven months of works.
The roads were closed as work took place to create a new roundabout which will provide access to the new Kilnwood Vale development.
However the slow journeys into Crawley will not end there as an eastbound lane has been closed on the A2220, which leads from the A264 to Breezehurst roundabout.
A spokesman for West Sussex County Council said the closure would continue until July 19 and was needed for the installation of underground pipes for the new development.