Toronto is a town in Clinton County, Iowa, United States. The population was 102 at the time of the 2020 census. Toronto was platted in 1853 …Toronto is a town in Clinton County, Iowa, United States. The population was 102 at the time of the 2020 census. Toronto was platted in 1853 by George W. Thorne, born in Maidstone, Kent, England in and raised in Toronto, Ontario, Canada. Thorne had built a sawmill and gristmill at the site in the 1840s.