List of cities in Ontario

A city is a subtype of municipalities in the Canadian province of Ontario. A city can have the municipal status of either a single-tier or lower-tier municipality. Prior to 2003, Ontario had minimum population thresholds of 15,000 and 25,000 for city status. Minimum population thresholds are no longer necessary for a municipality to brand itself as a city.

Ontario has 52 cities, which together had in 2016 a cumulative population of 9,900,179 and average population of 190,388. The most and least populous are Toronto and Dryden, with 2,794,356 and 7,749 residents, respectively. Ontario's newest city is Richmond Hill, whose council voted to change from a town to a city on March 26, 2019. Previous to that, Markham changed from a town to a city on July 1, 2012.