Niagara Falls is a city in Ontario, Canada, adjacent to, and named after, Niagara Falls. As of the 2021 census, the city had a population of 94,415. The city is located on the Niagara Peninsula along the western bank of the Niagara River, which forms part of the Canada–United States border, with the other side being the twin city of Niagara Falls, New York. Niagara Falls is within the Regional Municipality of Niagara and a part of the St. Catharines - Niagara Census Metropolitan Area.