The road opened just before 5 a.m.
The announcement came after day-long delays Wednesday on I-440 near the I-440/40 split.
Crews were doing patch work overnight, and expected to reopen the road before the morning commute, but the work did not go as planned and caused a delay.
The work is part of the so-called "Crawleigh" project to redo of 11 miles of Interstate 40 through Wake County. The massive overhaul of the interstate will mean heavy delays for commuters.
During the work, contractors will replace the pavement on I-40 between west of the Jones Franklin Road overpass and the exit for I-440/U.S. 64, and on I-440 between I-40/U.S. 64 and just north of U.S. 264 (Knightdale Bypass).
The project will also add extra travel lanes between ramps in each direction on I-40/U.S. 64 between U.S. 1/64 (Exit 293) and Lake Wheeler Road (Exit 297), as well as an extra westbound lane on I-40/U.S. 64 between the ramps at Rock Quarry Road (Exit 300) and the I-40/US 64/I-440 interchange (Exit 301).
In addition, 14 bridges on I-40 and I-440 will rehabilitated.
The DOT said the highway is 30 years old, and workers need to dig down at least two feet to remove and replace concrete and asphalt on the road, shoulders and ramps.
Officials estimate the project will take two and a half years to finish.