The roots of Ontario University Softball dates back to the year 2000, with discussions about creating a new league for softball athletes in universities in Ontario. Four schools founded the league in 2001, York University, the University of Toronto, McMaster University and the University of Ottawa to form what was then, the Ontario Intercollegiate Women’s Fastpitch Association.
In 2002, the league officially opened for play with eight teams ready for competition. The inaugural OUS champions were the Brock Badgers defeating McMaster in the first university softball championship in Ontario.
In 2022, the OIWFA officially changed it’s name to Ontario University Softball, and the OUS was born.