Mont. Code Ann. § 76-1-506
Filing of map of jurisdictional area of city-county planning board -- revision of boundaries
76-1-506 . Filing of map of jurisdictional area of city-county planning board -- revision of boundaries. The planning board, after approval of the jurisdictional area by the governing bodies, shall file in the office of the clerk and recorder a map showing the boundaries of the jurisdictional area. The boundaries may be revised from time to time by resolutions of the governing bodies. Such revised boundaries shall be shown upon a map which shall be filed as provided in this section. The area included in such map shall constitute the area over which the planning board shall have advisory jurisdiction.