US 287 north end, 1965-present
Choteau
US 91 north end, 1938-1980
Sweet Grass (there may be an historic border crossing here, but even if so, I don't know where it was)
US 87 north end, 1950s-present
Havre
Common: US 89 / US 87
Piegan. US 87 north end (1926-1934); US 89 north end (1934-present)
US 93 north end, 1926-present
Roosville
Common: US 191-20-287
West Yellowstone. US 191 north end (1926-1934); US 20 east end western segment (1942-present); US 287 south end northern segment (1965-present); US 191 south end (1981-1982)
US 191 north end, 1934-1963
Bozeman
US 191 north end, 1963-1997
Malta
US 191 north end, 1997-present
near Loring
US 89 south end, 1936-present
Gardiner (south end of northern segment)
Common: US 212-312-12
near Silver Gate. US 12 west end (1939-1959); US 312 west end (1959-1962); US 212 west end (1962-present)
US 310 north end, 1926-present
Laurel
US 312 west end, 1962-1981
Billings
US 312 east end, 1959-1962
Forsyth
US 312 east end, 1962-1981
Broadus
US 212 west end, 1939-1962
Miles City
US 12 west end, 1926-1939
Miles City
US 12 west end, 1959-1962
Missoula
US 87 north end, 1945(?)-1950s
Havre
Common: US 91-87
Great Falls. US 91 north end (1926-1938); US 87 north end (1934-1940s)