Châteauguay is a city located in southwestern Quebec, Canada. It serves as an off-island suburb of Montreal and is situated on both the Châteauguay River and Lac St-Louis, which constitutes a section of the St. Lawrence River.
According to the 2021 Census, the population of the city of Châteauguay was 50,815, while the total population for the surrounding population centre reached 75,891.