It runs from U.S. Route 191 at the United States border near Monchy to Highway 224 / Highway 904 in Meadow Lake Provincial Park.

[1] Major communities that Highway 4 passes through are Swift Current, Rosetown, Biggar, Battleford, North Battleford, and Meadow Lake.

It also passes The Battlefords Provincial Park.

[4] The designations were switched around c. 1940 to allow for the future Trans-Canada Highway to have the same number across western Canada.

[5] Several maps, such as MapArt's mapbook of Saskatchewan Cities and Towns shows a Highway 4S spur heading east from the intersection of Highway 4 in Swift Current to the city's airport, following Airport Road.