Leafs gave McFarland permission to interview Frontenacs after head coach fired Kurtis foster last month.
The 34-year-old from Richmond Hill, Ontario, McFarland was the Frontenac’s head coach for three seasons from 2014 to 2017 before serving as an assistant coach with the Florida Panthers.
McFarland has been with Florida for two seasons before joining the Leafs staff before the start of the 2019-20 campaign.
Leafs head coach Sheldon Keefe said the NHL break during the COVID-19 pandemic changed McFarland’s timeline.
“Normally, this type of move would be done during the off season, but since these are far from normal circumstances, we fully support Paul’s desire to continue this position in Kingston and gain more experience as a ‘head coach’, Keefe said in a statement.
McFarland made the playoffs in his three years at Kingston, reaching the second round twice.
“In the end, I made this decision for my own development as a head coach and I am honored and excited about the opportunity to help develop an exciting group of young players in Kingston. I’m still 100% committed to the Maple Leafs organization, staff and players for the rest of the 2019-2020 NHL season and the Stanley Cup Playoffs, “said McFarland in a statement.