Lavaltrie is a city located within the D'Autray Regional County Municipality in the southern part of the region of Lanaudière, Quebec, Canada, northeast of Montreal outside the suburban sprawl of the northern crown (i.e., the suburbs located north of Laval). The population was 13,267 as of the Canada 2011 Census within a land surface area of about 70 square kilometres, with the majority of the territory being used for agricultural activities.