League1 Ontario (L1O) was founded in November 2013 and is a semi-professional men’s and women’s soccer league in Ontario, Canada, and is sanctioned by the Canadian Soccer Association and the Ontario Soccer Association as a Division III league in the Canadian soccer league system. The 2021 season will include 20 teams in the men’s division and 15 teams in the women’s division.

In the Canadian soccer league system, its men’s division is behind the Canadian Premier League (CPL), and equal to the Première Ligue de soccer du Québec (PLSQ).