Ontario Highway 17B

Ontario Highway 17B

Highway 17B was formerly the highway designation for five business routes of Highway 17, the main route of the Trans-Canada Highway through the Canadian province of Ontario. Each was the original route of Highway 17 through the town or city that it served, and was subsequently given the 17B designation when a newer bypass route was constructed to reduce traffic pressure on the urban street network.

All five of the original 17B routes have been decommissioned by the Ministry of Transportation, and are now maintained only by their local municipalities. However, in some cases the "Highway 17B" name may still be informally used by local residents to refer to the routes, and old highway shields may still be visible along the route in some locations.

One additional highway route was given the Highway 17B designation in 2009, following a jurisdictional dispute between the Ministry of Transportation and the Garden River First Nation.