Population centre, in Canadian census data, is a populated place, or a cluster of interrelated populated places, which meets the demographic characteristics of an urban area, having a population of at least 1,000 people and a population density of no fewer than 400 persons per square km2.
Note that a population centre does not necessarily correspond to the political boundaries of a city or town; areas outside of a municipality may be included in its population centre where urban development is continuous, and areas inside a municipality may be excluded from its population centre if they are less densely populated. For example, the population centre of Toronto includes parts of the adjacent but politically distinct Durham, Halton, Peel and York regions, while the population centre of Ottawa does not include some communities within the city boundaries, such as Manotick, Osgoode or Goulbourn. A single municipality may also include more than one distinct population centre; for example, the cities of Ottawa, Hamilton and Greater Sudbury each have one "large urban" population centre and a number of separate "medium" or "small" population centres for smaller communities which are located within the city boundaries but are separated from the main urban core by a band of less urbanized or unpopulated area.
The term was first introduced in the Canada 2011 Census; prior to that, Statistics Canada used the term urban area.
In the 2011 census, Statistics Canada listed 270 population centres in the province of Ontario.