Montana Highway 89

Montana Highway System
Highway markers for MT 200, and S-323
Map of main highways (Interstate and U.S.)
System information
Maintained by MDT
Highway names
Interstates	Interstate n (I-n)
US Highways	U.S. Highway n (US n)
State	Montana Highway n (MT n)
Secondary:	Secondary Highway n (S-n)
System links
Montana Highway System Interstate U.S. State Secondary

The state highways in Montana are the state highways owned and maintained by the Montana Department of Transportation (MDT) in the U.S. state of Montana.

The square markers used today to identify primary Montana highways are only slightly different from their 1940s and earlier predecessors. The old markers used the word "ROUTE" above the number in big size, the route number in the middle, and the word "MONTANA" from edge-to-edge at the sign bottom. The font used was similar to that used for US routes.

The highway markers for Montana's S routes are distinctive in that the route number appears in black on a white down-pointing arrowhead. (Early markers were white numbers on black arrowheads with the word Montana in the flat top of the inverted arrowhead and Secondary appearing below the route number on the shields.)

S routes first appeared on the state highway map in 1960, even though the secondary system was established in 1942. With very few exceptions (i.e. MT 287, former MT 789), S routes are exclusively numbered 201 and higher.