List of municipalities in Ontario
Ontario is the most populous province in Canada with 12,851,821 residents as of 2011 and is third-largest in land area at approximately 909,000 km2 (351,000 sq mi). Ontario's 444 municipalities cover only 17% of the province's land mass yet are home to 99% of its population. These municipalities provide local or regional municipal government services within either a single-tier or shared two-tier municipal structure.
A municipality in Ontario is "a geographic area whose inhabitants are incorporated" according to the Municipal Act, 2001. Ontario's three municipality types include upper and lower-tier municipalities within the two-tier structure and single-tier municipalities (unitary authorities) that are exempt from the two-tier structure. Single and lower-tier municipalities are grouped together as local municipalities. Of Ontario's 444 municipalities, 30 of them are upper-tier municipalities and 414 are local municipalities — 241 lower-tier municipalities and 173 single-tier municipalities.
The Municipal Act, 2001 is the legislation that enables incorporation and stipulates governance of Ontario's municipalities, excluding the City of Toronto, which is subject to the City of Toronto Act, 2006. The Municipal Act, 2001 provides lower and single-tier municipalities with the authority to incorporate as cities, towns, villages, townships, or generically as municipalities. There are no minimum population thresholds or other requirements for these municipal sub-types. A municipality can change its status to any of these so long as its resulting name is not being used by another municipality. For upper-tier municipalities, the act provides them with the authority to incorporate as counties, regions and district municipalities.
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