Niagara United FC is a Canadian soccer team founded in 1973. The club is a former member of the Canadian Soccer League (CSL), where it fielded a professional team from 2011-2015, and now operates youth teams in the Niagara Soccer League. The team plays its home games in Kalar Sports Park in Niagara Falls, Ontario. In 2011, the club joined the CSL and played in the CSL Second Division. After a successful debut season Niagara was promoted to the First Division, and qualified for the playoffs in their first season in the top flight. The following season the club went through a rebuilding stage focusing on developing and recruiting local players. In 2016, Niagara announced its departure from the league.

The Canadian Soccer League is a semi-professional league for Canadian soccer clubs primarily located in the province of Ontario, and claims the history of the Canadian National Soccer League (CNSL). It is a non-FIFA league previously sanctioned by the Canadian Soccer Association (CSA), but now affiliated with the Soccer Federation of Canada (SFC). As of 2023, it consists of seven teams, all located in Ontario. The season usually runs from May to October, with most games played on the weekend followed by a playoff format to determine the overall champion.