King's Highway 412, or simply Highway 412, is a controlled-access highway and former tolled highway in the Canadian province of Ontario. The route is 8.9 km (5.5 mi) long, connecting Highway 401 with the eastern extension of Highway 407. The route lies entirely within Whitby in the Regional Municipality of Durham, travelling within one kilometre of the border between Whitby and Ajax and Pickering (Lake Ridge Road).