Ontario is the largest city in Malheur County, Oregon, United States. It lies along the Snake River at the Idaho border. The population was 11,64…Ontario is the largest city in Malheur County, Oregon, United States. It lies along the Snake River at the Idaho border. The population was 11,645 at the 2020 census. The city is the largest community in the region of far eastern Oregon, also known as the Western Treasure Valley.
Save
Share
More