A map of southern Ontario that shows FedDev Ontario's scope of operations, from Cornwall in the east to Owen Sound in the west, and from Pembroke in the north to Windsor in the south. According to Statistics Canada's annual population estimates for 2009, southern Ontario has a population of more than 12 million people, representing approximately 93% of Ontario's total population and 36% of the total population of Canada.

List of the 37 Statistics Canada census divisions of southern Ontario:

Stormont, Dundas and Glengarry, Kawartha Lakes, Niagara, Middlesex, Prescott and Russell, Peterborough, Haldimand-Norfolk, Huron, Ottawa, Durham, Brant, Bruce, Leeds and Grenville, York, Waterloo, Grey, Lanark, Toronto, Perth, Simcoe, Frontenac, Peel, Oxford, Haliburton, Lennox and Addington, Dufferin, Elgin, Renfrew, Hastings, Wellington, Chatham-Kent, Prince Edward, Halton, Essex, Northumberland, Hamilton, Lambton.