Repentigny is an off-island suburb of Montreal, Quebec, Canada. It is located north of the city on the lower end of the L'Assomption River, and on the Saint Lawrence River. Repentigny and Charlemagne were the first towns off the eastern tip of the Island of Montreal. Repentigny is part of the Lanaudière region.

Greater Montreal is the most populous metropolitan area in Quebec and the second most populous in Canada after Greater Toronto. In 2015, Statistics Canada identified Montreal's Census Metropolitan Area (CMA) as 4,258.31 square kilometres (1,644.14 sq mi) with a population of 4,027,100, almost half that of the province.