The 2013 CIS football season began on August 25, 2013, with ten Ontario University Athletics teams playing that day. The season concluded on November 23 with the 49th Vanier Cup championship in Quebec City, won by the Laval Rouge et Or after they defeated the Calgary Dinos 25–14. This year, 27 university teams in Canada played Canadian Interuniversity Sport football, the highest level of amateur Canadian football. The Carleton Ravens football team re-joined the CIS after a 14-year absence, increasing the number of OUA teams to 11 and necessitating the use of bye weeks in that conference.