Around 10 a.m. on May 19, emergency crews responded to a collision on the highway just north of Thunder Bridge Road, about five kilometres north of Lindsay.
Police say the collision involved a car, an SUV and an SUV towing a trailer.
All three involved drivers were transported to hospital. One had minor injuries, another was transported to a Toronto-area trauma centre and another was pronounced dead at the hospital.
On Friday, OPP identified the victim as Monica Sooley, 35, of Lindsay, Ont.
The cause of the collision remains under investigation, police said.
A GoFundMe page in support of Sooley’s family has raised more than $23,000 of its $25,000 goal. Sooley is survived by her husband Bradley, and two children, Owen, 6, and Colin, 4, according to an online obituary.