Current Ontario Counties, Districts, and Municipalities

Counties

Bruce· Dufferin· Essex· Frontenac· Grey· Haliburton· Hastings· Huron· Lambton· Lanark· Leeds and Grenville· Lennox and Addington· Middlesex· Northumberland· Perth· Peterborough· Prescott and Russell· Reffrew· Simcoe· Stormont, Dundas and Glengarry· Wellington

Districts

Algoma· Cochrane· Kenora· Manitoulin· Nipissing· Parry Sound· Rainy River· Sudbury· Thunder Bay· Timiskaming

Regional municipalities

Durham· Halton· Muskoka· Niagara· Oxford· Peel· Waterloo· York

Single-tier municipalities

Brant· Brantford· Chatham-Kent· Greater Sudbury· Haldimand· Hamilton· Kawartha Lakes· Norfolk· Ottawa· Prince Edward· Toronto

Separated municipalities

Barrie· Belleville· Brockville· Gananoque· Guelph· Kingston· London· Orillia· Pembroke· Peterborough· Prescott· Quinte West· Smiths Falls· St. Marys· St. Thomas· Stratford· Windsor

Extinct jurisdictions

Addington County· Bothwell District· Brant County· Cardwell District· Carleton County· Dufferin County· Dundas County· Durham County· Frontenac County· Glengarry County· Grenville County· Haldimand County· Halton County· Kent County· Leeds County· Lennox County· Lincoln County· Monck District· Niagara District· Norfolk County· Ontario County· Patricia County· Peel County· Prescott County· Prince Edward County· Russell County· Stormont County· Sudbury Regional Municipality· Suffolk County· Victoria County· Welland County· Waterloo County· Wentworth County· York County