With a deadline of early Wednesday morning, talks continued late into the night between Unifor and Jamieson Laboratories Ltd. in Windsor.
Then sometime around midnight a breakthrough and it was announced that a tentative deal had been reached.
The details of the deal will remain unknown pending a ratification vote on Sunday.
Local 195 President Gerry Farnham said Tuesday that he had been pleased with the progress of the negotiations.
Farnham represents 240 workers and their contracts were set to expire minute passed midnight.
Jamieson is a manufacturer of natural health products.
