According to Elections Canada, Oak Ridges—Markham consisted of that part of the Regional Municipality of York composed of: (a) the Town of
Whitchurch–Stouffville; (b) the part of the Township of
King south of Highway No. 9; (c) the part of the Town of
Richmond Hill lying north and east of a line drawn from the western town limit east along Gamble Road, south along Yonge Street and east along Elgin Mills Road East to the eastern town limit; and (d) the part of the City of
Markham lying north and east of a line drawn from the western town limit east along 16th Avenue, south along McCowan Road, east along Highway No. 7, and south along 9th Line to the southern town limit. ==Members of Parliament==