St. Clair is a subway station on Line 1 Yonge–University in Toronto, Ontario, Canada. The station opened in 1954 as part of the original Yonge Street subway.

Line 1 Yonge–University is a rapid transit line of the Toronto subway. It serves Toronto and the neighbouring city of Vaughan in Ontario, Canada. It is operated by the Toronto Transit Commission, has 38 stations and is 38.4 km (23.9 mi) in length, making it the longest line on the subway system. It opened as the "Yonge subway" in 1954 as Canada's first underground passenger rail line and was extended multiple times between 1963 and 2017. Averaging over 680,000 riders per weekday, Line 1 is the busiest rapid transit line in Canada, and one of the busiest lines in North America.