Ontario Highway 413

Highway 413
GTA West Corridor      Highway 410 and 427 extensions (proposed)
Route information
Maintained by Ministry of Transportation of Ontario
Length	52 km[1] (32 mi)
History	Proposed January 2002[2] Cancelled February 9, 2018[3] Revived November 2018[4]
Major junctions
West end	Highway 401 / 407 ETR in Halton Hills
Major intersections	Highway 410 south in Caledon  Highway 427 south near Bolton
East end	Highway 400 in Vaughan
Location
Country	Canada
Province	Ontario
Highway system
Ontario provincial highways Current Former 400-series
← Highway 412 → Highway 416

King's Highway 413, known as the GTA West Corridor or GTA West until 2021, is a proposed 400-series highway and bus transitway in the western Greater Toronto Area of the Canadian province of Ontario. The approximately 52-kilometre (32 mi) route is currently undergoing planning and analysis under an environmental impact assessment (EA) by the Ministry of Transportation of Ontario (MTO) and the Government of Ontario. If approved, a new four-to-six lane controlled-access highway would be built between the existing interchange of Highway 401 and the 407 ETR at the Halton–Peel boundary, and Highway 400 north of Vaughan. In addition, two new extensions would be built to connect Highway 410 and Highway 427 with Highway 413.

The proposed highway would serve as an outer ring road around the built-up areas of Brampton and Vaughan that would permit traffic travelling between Southwestern Ontario and Ontario's cottage country or Northern Ontario to bypass much of the Greater Toronto Area. However, the highway has attracted criticism for its environmental impacts, including concerns about its footprint on designated farmland in the Greenbelt, and its implications to encourage urban sprawl and induced demand.

Planning for the corridor began in the mid 2000s. However the EA was suspended in 2015, and the project shelved in February 2018 by the Liberal government of Kathleen Wynne. Following the 2018 Ontario general election in June of that year, the new Progressive Conservative government of Doug Ford announced the resumption of the suspended EA in November. Since then, several of the municipalities along the route have voiced their opposition to its construction. In April 2024, a previously announced federal EA was dropped by the Canadian government, with the federal and provincial governments to work together to minimize environmental impacts along the corridor instead. Construction is set to begin in 2025.