Work has finished three weeks early on the new £1.3m roundabout at Barnetby Top on the A18.
It is now open to traffic as normal.
.Work started to build the new roundabout in February 2016.
Councillor Neil Poole, cabinet member for Environment at North Lincolnshire Council, said: “I’m pleased work has now finished, and three weeks earlier than expected. This is great news.
“This is a huge investment that will help improve safety and traffic flow at this junction, particularly for those travelling from Brigg to the motorway.
“Everyone has worked hard to get the work finished early and contractors have been working six days a week to get the job done.
“This has not been an easy scheme due to its location at a busy junction and on the edge of Barnetby village. I want to take this opportunity to thank people for their patience and understanding.”