Wikipedia:WikiProject U.S. Roads/Montana/All-time list
Given are the years of the first and last official maps (also [1] is a little blurry but has a few that aren't on the MDT site) the routes appear on. These are not always the exact years the routes were created or eliminated.
A 1927 and 1930 map and a 1929 map show an almost completely different numbering system.
A 1932 Gousha/Conoco map shows some routes; these are marked with an asterisk. Note that all except 22 (which was kept in the numbering system) were odd.
Secondary routes first appear on maps in 1960, but federal aid logs are available back to 1938 (1943 is the first with secondaries) (post-1993 logs). Therefore all secondary years are based on the logs, but primary years are based on maps.
haven't gone through these: 2011 log 2013 log
| from | to | notes | |
|---|---|---|---|
| MT 1 | 1987 ← US 10A |
now | |
| MT 1 | 1936 ← 191 |
1958 → 287 (part) |
1 may have been skipped in the original numbering |
| MT 2 | 1987 ← US 10 (part) |
now | parts are not state maintained 2 was skipped in 1934 because of US 2 |
| MT 3 | 1957 | now | |
| MT 3 | 1931 ← 33 (part) |
1940 → US 10A |
numbered to match Idaho |
| MT 4 | 1931? | 1938 | Idaho to Thompson Falls; now 471 numbered to match Idaho |
| MT 5 | 1931 ← 17 |
now | numbered to match North Dakota |
| MT 6 | 1931? ← 33 (part) |
1959 → US 12 (part) | |
| MT 7 | 1931 ← 10 (part) |
now | |
| MT 8 | 1934 | 1961 → US 212 (part) | |
| MT 9 | 1931 ← 91 |
1938 | Idaho to Lolo; became 412 in 1947 numbered to match Idaho |
| MT 10 | 1927 | 1931 → 7 | |
| MT 10 | when? | now? | |
| MT 11 | 1927 | 1931 → US 12 (part) |
portion removed in 1930 was US 10 west of Miles City and US 12 east of Ismay |
| MT 11 | 1931 ← 76 |
1932 → US 91 (part) | |
| MT 11 | 1936 | when? | where? was one of the unlabeled roads |
| MT 12 | 1927 | 1931 → 15 | |
| MT 13 | 1934 | now | unlabeled road in 1929 |
| MT 13W | 1954 ← 13 (part) |
1993 → 25 | |
| MT 14 | 1927 | 1953 → 16 (part), 23N |
portion removed in 1930 was US 10 from Miles City to Glendive |
| MT 15 | 1931 ← 12 |
1938 | Stanford to Chester; now 80, 223 |
| MT 16 | 1927 | now | |
| MT 17 | 1927 | 1931 → 5 | |
| MT 17 | 1931 ← 20 |
1932 | Redstone to Canada |
| MT 17 | 1936 | now | not state maintained since 1963 |
| MT 18 | 1927 | 1931 | Sidney via Girard and Poplar to Scobey; now 201 and county roads |
| MT 18 | 1934 ← 55 |
1958 → 20 (part), 20S | |
| MT 19 | 1963 ← 191 |
now | |
| MT 19 | 1931 ← 32 |
1962 → US 191 (part) | |
| MT 20 | 1927 | 1931 → 17 |
Redstone to Canada |
| MT 20 | 1931 ← 33 (part), 69 |
1967 → 200 | |
| MT 20S | 1959 ← 18 (part) |
1967 → 200S | |
| MT 21 | 1949 | now | |
| MT 21 | 1931 | 1938 | Columbus to Ryegate; now 300, 306 |
| MT 22 | 1927 | 1985 → 59 (part) |
part of original numbering system; retained |
| MT 23 | 1931 | now | numbered to match North Dakota disappeared in 1948; part of 16 in 1950; returned in 1951 mainline 23 became part of 20 in 1959, but 23S became 23 in 1960 |
| MT 23N | 1954 ← 14 (part) |
1959 → 20 (part) | |
| MT 23S | 1954 ← 23 (part) |
1959 → 23 | |
| MT 24 | 1949 ← 22 (part) |
now | |
| MT 24 | 1931 ← 77 |
1938 | Jennings (Libby Dam) to Marion |
| MT 24W | 1978 ← 24 (part) |
1993 → 42 | |
| MT 25 | 1994 ← 13W |
now | |
| MT 25 | 1931 ← 30 |
1938 | Billings to Lewistown; now 3, 238 (part) |
| MT 26 | 1931 | 1938 | Trout Creek to Manicke |
| MT 27 | 1931 ← 34 |
1938 | Winifred to Big Sandy; now 236 |
| MT 28 | 1931 | now | |
| MT 29 | 1931 ← 68 |
1947 → US 87 (part) |
1956 shows 29 on current 324, but that's probably simply the shield being on the wrong side of the border |
| MT 30 | 1927 | 1931 → 25 |
old route removed in 1930 and was concurrent with US 87E (south of Grassrange only) |
| MT 30 | 1931 ← 10 (part) |
1938 | Miles City to South Dakota via Ekalaka |
| MT 31 | 1931 ← 86 (part) |
1938 | Bigfork to Drummond; now 83, 141, 200, 271 |
| MT 32 | 1927 | 1931 → 19 | |
| MT 32 | 1931 ← 42 |
1938 → US 12 (part) | |
| MT 33 | 1927 | 1931 → 3, 6, 20 | |
| MT 33 | 1931 ← 88 |
1958 → 287 (part) | |
| MT 34 | 1927 | 1931 → 27 | |
| MT 34 | 1931 ← 71 |
1961 → 287 (part) | |
| MT 35 | 1927 | 1931 | Helena to White Sulphur Springs; now Canyon Ferry Road, 284, Confederate Gulch Road, Benton Gulch Road, and 360 |
| MT 35 | 1931 ← 92 |
now | disappeared in 1939, but returned in 1951 (had been 210) |
| MT 36 | 1931 ← 90 |
1938 | Lost Trail Pass to Dillon; now 43, 278 |
| MT 37 | 1931 ← 94 |
now | |
| MT 38 | 1931 ← 87 |
now | not state maintained since 1975-1976 |
| MT 39 | 1931 | 1938 → 19 (part) |
Hysham to Canada via Malta; now US 191, 245 |
| MT 39 | 1978 ← 315 |
now | numbered the same as its federal aid number (assigned 1976) |
| MT 40 | 1927 | 1930 → US 310 | |
| MT 40 | 1936 | now | Became part of 37 in 1939-40 but became 40 again in 1947-48; unlabeled until 1949 |
| MT 41 | 1931 ← 72 |
now | |
| MT 42 | 1927 | 1931 → 32 | |
| MT 42 | 1936 | when? | where? was one of the unlabeled roads |
| MT 42 | 1994 ← 24W |
now | |
| MT 43 | 1931 ← 86 (part) |
now | disappeared in 1939, but returned in 1949 |
| MT 44 | 1936 | when? | where? was one of the unlabeled roads |
| MT 44 | 1978 ← 216 |
now | numbered the same as its federal aid number (assigned 1976) |
| MT 45 | 1931 ← 57 |
1938 | Lame Deer to Forsyth; now 39 (part), 447 |
| MT 46 | 1936 | when? | where? was one of the unlabeled roads |
| MT 47 | 1934 | now | disappeared in 1939, but returned in 1948 |
| MT 48 | 1936 | now | unlabeled until 1949 |
| MT 49 | 1936 | 1936 → 41 (part) |
41 followed current 55 at the time |
| MT 49 | 1940 | now | unlabeled until 1949; swapped with US 2 in 1950-1951 not state maintained since 1975-1976 |
| MT 50 | 1936 | 1953 → 13 (part) |
east of Wolf Point; unlabeled until 1953 |
| MT 50 | 1966 ← 287 (part) |
1967 → 87 | |
| MT 55 | 1927 | 1931 → 18 |
sections to the west and east replaced by US 87E and US 10 |
| MT 55 | 1978 ← 287 (part) |
now | numbered the same as its federal aid number (assigned 1976) |
| MT 56 | 1978 ← 202 |
now | numbered the same as its federal aid number (assigned 1976) |
| MT 57 | 1927 | 1931 → 45 | |
| MT 59 | 1967 ← 319 |
now | numbered to match Wyoming |
| MT 60 | 1927 | 1931 → 187 | |
| MT 61 | 1927 | 1931 | Brady to Carter; now partially 564 |
| MT 62 | 1927 | 1931 | Watson to Ulm; now 360 |
| MT 63 | 1927 | 1931 | Conrad to north of Dupuyer; now 534 |
| MT 64 | 1981 | now | numbered the same as its federal aid number (assigned 1976 from former P-50 Spur) |
| MT 66 | 1927 | 1930 → US 87W, US 87 | |
| MT 66 | 1978 ← 376 |
now | numbered the same as its federal aid number (assigned 1976) |
| MT 68 | 1927 | 1931 → 29 |
Section southwest to Wolf Creek was removed in 1930 and was concurrent with US 91 |
| MT 68 | 2001? | now | unlabeled at first; color changes to red in 2001 numbered the same as its federal aid number (assigned 1976) |
| MT 69 | 1927 | 1931 → 20 (part) | |
| MT 69 | 1978 ← 281 |
now | numbered the same as its federal aid number (assigned 1976) |
| MT 70 | 1927 | 1931 → 191 | |
| MT 71 | 1927 | 1931 → 34 | |
| MT 72 | 1927 | 1931 → 41 | |
| MT 72 | 1978 ← 308 (part), 397 |
now | numbered the same as its federal aid number (assigned 1976) |
| MT 76 | 1927 | 1931 → 11 | |
| MT 77 | 1927 | 1931 → 24 |
Original route was councurrent with US 2; rerouted in 1929 and section concurrent with US 2 removed 1930 |
| MT 78 | 1978 ← 307 |
now | numbered the same as its federal aid number (assigned 1976) |
| MT 80 | 1978 ← 230 |
now | numbered the same as its federal aid number (assigned 1976) |
| MT 81 | 1978 ← 235 |
now | numbered the same as its federal aid number (assigned 1976) |
| MT 82 | 1978 ← 208 |
now | numbered the same as its federal aid number (assigned 1976) |
| MT 83 | 1978 ← 209 (part), 326 |
now | numbered the same as its federal aid number (assigned 1976) |
| MT 84 | 1978 ← 289 |
now | numbered the same as its federal aid number (assigned 1976) |
| MT 85 | 1978 ← 291 (part) |
now | numbered the same as its federal aid number (assigned 1976) |
| MT 86 | 1927 | 1931 → 31, 110, 43 | |
| MT 86 | 1978 ← 293 |
now | numbered the same as its federal aid number (assigned 1976) |
| MT 87 | 1927 | 1931 → 38 | |
| MT 87 | 1968 ← 50 |
now | |
| MT 88 | 1927 | 1931 → 33 | |
| MT 90 | 1927 | 1931 → 36 |
Section north of there was concurrent with US 93 and was removed in 1930 |
| MT 91 | 1927 | 1931 → 9 | |
| MT 92 | 1927 | 1931 → 35 | |
| MT 94 | 1927 | 1931 → 37 | |
| MT 110 | 1931 ← 86 (part) |
1936 → US 10A |
now 1 |
| MT 117 | 1978 ← 249 |
now | numbered from its federal aid number P-17 (assigned 1976) |
| MT 135 | 1978 ← 461 |
now | numbered from its federal aid number P-35 (assigned 1976) |
| MT 141 | 1978 ← 271 (part), 272 |
now | numbered from its federal aid number P-41 (assigned 1976) |
| MT 187 | 1931 ← 60 |
1938 | mostly became US 191 in 1934-1935; rest is now 86 |
| MT 191 | 1961 | 1962 → 19 | |
| MT 191 | 1931 ← 70 |
1935 → 1 | |
| MT 200 | 1968 ← 20 |
now | |
| MT 200S | 1968 ← 20S |
now | |
| S-201 | 1952 | now | maintained (but not signed) as a primary route east of MT 16 |
| S-202 | 1977 | now | |
| S-202 | 1945 | 1975 → 56 | |
| S-203 | 1952 | now | |
| S-204 | 1952 | now | |
| S-205 | 1976 ← US 10 (part) |
now | |
| S-205 | 1943 | 1945 | north from Plains |
| S-206 | 1943 | now | swapped with US 2 in 1981-1983 |
| S-207 | 1978 | now | |
| S-207 | 1943 | 1975 | Southeast from Kalispell |
| S-208 | 1978 | now | |
| S-208 | 1943 | 1975 → 82 | |
| S-209 | 1945 | now | |
| S-210 | 1976 ← US 10-12 (part) |
now | |
| S-210 | 1943 | 1950 → 35 | |
| S-211 | 1943 | now | |
| S-212 | 1943 | now | |
| S-213 | 1943 | now | |
| S-214 | 1943 | now | originally west from Sweetgrass, but gradually moved to west from Sunburst and original route became part of 213, then moved back in 1975-1976 when 213 replaced 483 |
| S-215 | 1943 | now | |
| S-216 | 1981 | 1993 | 279 to Marysville |
| S-216 | 1943 | 1975 → 44 | |
| S-217 | 1976 ← 343 (part) |
now | |
| S-217 | 1943 | 1945 | became 534 in 1964 |
| S-218 | 1945 | now | |
| S-219 | 1943 | now | |
| S-220 | 1943 | now | |
| S-221 | 1943 | now | |
| S-222 | 1976 ← US 91 (part) |
now | |
| S-222 | 1943 | 1945 | became 431 in 1955 |
| S-223 | 1943 | now | |
| S-224 | 1943 | now | |
| S-225 | 1943 | now | |
| S-226 | 1943 | now | |
| S-227 | 1943 | now | |
| S-228 | 1945 | now | |
| S-229 | 1976 ← US 91 (part) |
now | |
| S-229 | 1943 | 1954 → 223 (part) |
northwest from Fort Benton |
| S-230 | 1982 | 1993 | unbuilt north frontage road, east of Laurel to 40th Street Billings |
| S-230 | 1945 | 1975 → 80 | |
| S-231 | 1983 | now | |
| S-231 | 1943 | 1975 | became 255 in 1984 |
| S-232 | 1943 | now | |
| S-233 | 1943 | now | |
| S-234 | 1943 | now | |
| S-235 | 1983 | now | |
| S-235 | 1943 | 1975 → 81 | |
| S-236 | 1943 | now | |
| S-237 | 1943 | now | |
| S-238 | 1943 | now | |
| S-239 | 1943 | now | |
| S-240 | 1943 | now | |
| S-241 | 1943 | now | |
| S-242 | 1943 | 1993 → US 191 (part) | |
| S-243 | 1943 | now | |
| S-244 | 1943 | now | |
| S-245 | 1943 | now | |
| S-246 | 1943 | now | |
| S-247 | 1983 | now | typoed as 246 in 1983 log |
| S-247 | 1943 | 1975 → 24 (part) |
listed as being part of MT 22 in 1943 |
| S-248 | 1943 | now | |
| S-249 | 1984 | now | |
| S-249 | 1943 | 1975 → 117 | |
| S-250 | 1943 | now | |
| S-251 | 1943 | now | |
| S-252 | 1943 | now | |
| S-253 | 1943 | now | |
| S-254 | 1943 | now | |
| S-255 | 1984 | now | had been 231 until 1975-1976 |
| S-255 | 1943 | 1945 | Outlook to Raymond |
| S-256 | 1943 | 1975 → 16 (part) |
listed as being part of MT 16 in 1943 was this number reused in 1984? |
| S-257 | 1952 | now | |
| S-258 | 1943 | now | |
| S-259 | 1984 | now | |
| S-259 | 1943 | 1954 → 201 (part) |
west from Fairview |
| S-260 | 1986 | now | had been 506 until 1975-1976 |
| S-260 | 1943 | 1950 → 23 (part) |
Lambert to Sidney |
| S-261 | 1943 | now | |
| S-262 | 1943 | 1975 | Southside Road, northwest from Superior |
| S-263 | 1943 | now | |
| S-264 | 1943 | 1974 → FAU 8102 |
3rd Street and Clements Road, Higgins Avenue to South Avenue, Missoula |
| S-265 | 1943 | 1974 → FAU 8120 |
South Avenue, Higgins Avenue to Clements Road, Missoula |
| S-266 | 1943 | 1974 → FAU 8117 |
Higgins Avenue, Russell Street to Brooks Street, Missoula |
| S-267 | 1943 | 1993 | Van Buren Street and Rattlesnake Drive, northeast from Missoula disappeared in 1976, but reappeared in 1978 |
| S-268 | 1943 | 1975 → 203 (part) | |
| S-269 | 1943 | now | |
| S-270 | 1953 | 1993 | 323 to Capitol |
| S-271 | 1945 | now | |
| S-272 | 1987 | now | why this number? missing from current state map |
| S-272 | 1945 | 1975 → 141 (part) | |
| S-273 | 1943 | now | |
| S-274 | 1943 | 1985 | became 569 in 2001 |
| S-275 | 1987 | now | why this number? |
| S-275 | 1943 | 1975 | Stewart Street, east of Anaconda |
| S-276 | 1943 | now | |
| S-277 | 1953 | now | |
| S-278 | 1943 | now | |
| S-279 | 1943 | now | |
| S-280 | 1943 | now | |
| S-281 | 1943 | 1975 → 69 | |
| S-282 | 1987 | now | why this number? |
| S-282 | 1943 | 1945 → 41 (part) |
41 and Burma Road southwest from Twin Bridges |
| S-283 | 1943 | now | |
| S-284 | 1943 | now | |
| S-285 | 1943 | now | |
| S-286 | 1943 | now | |
| MT 287 | 1959 ← 1, 33 |
now | |
| MT 287A | 1962 ← 287 (part) |
1965 → US 287 | |
| S-287 | 1943 | now | |
| S-288 | 1943 | now | |
| S-289 | 1943 | 1975 → 84 | |
| S-290 | 1943 | now | |
| S-291 | 1943 | 2001 | south from Belgrade; mostly became 85 in 1975-1976 |
| S-292 | 1996 | now | why this number? |
| S-292 | 1953 | 1975 | Ekalaka to Mill Iron |
| S-293 | 1945 | 1975 → 86 | |
| S-294 | 1943 | now | |
| S-295 | 1943 | now | |
| S-296 | 1943 | 1975 | south from Two Dot |
| S-297 | 1943 | now | |
| S-298 | 1943 | now | |
| S-299 | 1943 | 1975 → 238 (part) | |
| S-300 | 1943 | now | |
| S-301 | 1943 | 1956 → 3 | |
| S-302 | 1943 | now | |
| S-303 | 1943 | 1975 | 8th Road?, I Road, and Fly Creek Road, Huntley to Nibbe |
| S-304 | 1943 | 1975 | Shepherd Road, old US 312 to Scandia Road, northwest of Huntley |
| S-305 | 1943 | 1975 → 532 (part) |
72nd Street and King Avenue (532), Laurel to Billings |
| S-306 | 1945 | now | |
| S-307 | 1943 | 1975 → 78 | |
| S-308 | 1943 | now | |
| S-309 | 1943 | 1972 | northwest from Roundup |
| S-310 | 1943 | now | |
| S-311 | 1943 | now | |
| S-312 | 1943 | 1962 | Gumbo Hill Road, southeast from Hysham north end became part of P-2, carrying US 10-312 (at least until I-94 was built east of Hysham); now part of 311 |
| S-313 | 1943 | now | |
| S-314 | 1946 | now | |
| S-315 | 1943 | 1975 → 39 | |
| S-316 | 1943 | 1945 | became 446 in 1956 |
| S-317 | 1953 | now | |
| S-318 | 1953 | 1974 → FAU 1014 |
Airport Road, Billings |
| S-319 | 1943 | 1966 → 59 | |
| S-320 | 1943 | now | |
| S-321 | 1943 | 1975 | northeast from Plevna |
| S-322 | 1943 | now | |
| S-323 | 1943 | now | |
| S-324 | 1945 | now | |
| S-325 | 1946 | now | |
| S-326 | 1990 | now | why this number? had been 492 until 1975-1976 |
| S-326 | 1954 | 1975 → 83 (part) | |
| S-327 | 1953 | now | |
| S-328 | 1994 | now | why this number? |
| S-328 | 1953 | 1975 | Acton to Broadview |
| S-329 | 1953 | 1975 | Duck Creek Road, east of Laurel |
| S-330 | 1945 | now | |
| S-331 | 1945 | now | |
| S-332 | 1945 | now | |
| S-333 | 1945 | 1983 | east of Miles City |
| S-334 | 1994 | now | why this number? |
| S-334 | 1945 | 1962 → 13 (part) |
north from Scobey |
| S-335 | 1945 | now | |
| S-336 | 1945 | now | |
| S-337 | 1956 | 1957 | Basin Creek Road, west from Volborg |
| S-338 | 1954 | now | |
| S-339 | 1954 | 1975 | northeast from Wilsall |
| S-340 | 1954 | now | |
| S-341 | 1954 | now | |
| S-342 | 1954 | now | missing from the current state map |
| S-343 | 1954 | now | |
| S-344 | 1954 | now | |
| S-345 | 1946 | now | |
| S-346 | 1946 | now | |
| S-347 | 1945 | now | |
| S-348 | 1945 | now | |
| S-349 | 1954 | 1975 | Plentywood to Comertown |
| S-350 | 1954 | now | |
| S-351 | 1945 | 1954 → 236 (part) |
southeast from Big Sandy |
| S-352 | 1945 | now | |
| S-353 | 1945 | 1975 | northwest from Moiese |
| S-354 | 1945 | now | |
| S-355 | 1954 | 1974 → FAU 5802 |
Custer Avenue, Montana Avenue to Henderson Street, Helena |
| S-356 | 1945 | 1975 | Williams Street and Birdseye Road, northwest from Helena |
| S-357 | 1945 | now | |
| S-358 | 1954 | now | |
| S-359 | 1945 | now | |
| S-360 | 1945 | now | |
| S-361 | 1975 | 1983 | Melrose to Twin Bridges |
| S-361 | 1945 | 1947 → 209 (part) |
northwest from 20 |
| S-362 | 1945 | 1975 | became 571 in 2001 |
| S-363 | 1945 | now | |
| S-364 | 1945 | 1975 | south from Malta |
| S-365 | 1945 | now | |
| S-366 | 1945 | now | |
| S-367 | 1945 | 1975 | northeast of Corvallis |
| S-368 | 1945 | 1975 | east from Hamilton |
| S-369 | 1954 | 1975 | east of Conrad |
| S-370 | 1945 | now | |
| S-371 | 1954 | 1975 | west from Melville |
| S-372 | 1945 | 1975 | east from Stevensville |
| S-373 | 1945 | now | |
| S-374 | 1945 | now | |
| S-375 | 1954 | 1993 | Continental Drive, Butte (where was the north end pre-1974?) |
| S-376 | 1956 | 1975 → 66 | |
| S-377 | 1955 | 1975 | southeast of Stevensville |
| S-378 | 1945 | 1975 → 220 (part) | |
| S-379 | 1945 | now | |
| S-380 | 1955 | 1975 | northeast of Hamilton |
| S-381 | 1945 | now | disappeared in 1976, but returned in 1979 |
| S-382 | 1945 | now | |
| S-383 | 1955 | 1975 | southeast of Hamilton |
| S-384 | 1945 | now | |
| S-385 | 1945 | 1975 | west of Highwood |
| S-386 | 1945 | now | |
| S-387 | 1945 | now | |
| S-388 | 1955 | 1975 | southeast of Hamilton |
| S-389 | 1945 | 1975 | southeast of Cut Bank |
| S-390 | 1945 | 1974 → FAU 8109 |
39th Street and Russell Street, Brooks Street to Broadway Street, Missoula |
| S-391 | 1945 | now | |
| S-392 | 1946 | 1963 | Butte Municipal Airport entrance from Harrison Avenue (US 10) |
| S-393 | 1945 | now | |
| S-394 | 1945 | 1975 | south from Shawmut |
| S-395 | 1946 | 1962 | 30th Street and Poly Drive, Montana Avenue to 17th Street, Billings |
| S-396 | 1946 | now | |
| S-397 | 1945 | 1975 → 72 (part) | |
| S-398 | 2000 | now | why this number? had been 402 until 1985-1987 |
| S-398 | 1946 | 1956 → 273 (part) |
east of Anaconda |
| S-399 | 1946 | now | disappeared in 1976, but returned in 1993 |
| S-400 | 1946 | now | |
| S-401 | 1987 | now | why this number? |
| S-401 | 1946 | 1975 → 55 |
southwest from Whitehall signed as part of 287 from 1961 to 1967 |
| S-402 | 1946 | 1985 | became 398 in 2000 |
| S-403 | 1946 | 1974 → FAU 1801 |
Main Street, Daly Street, Walkerville Drive, and Excelsior Avenue, Park Street to Hornet Street?, Butte-Walkerville |
| S-404 | 1946 | 1975 → 344 (part) | |
| S-405 | 1946 | now | |
| S-406 | 1946 | 1965 → 405 (part) |
east from Froid |
| S-407 | 1946 | 1975 | Beck Hill Road, north of Deer Lodge |
| S-408 | 1946 | now | |
| S-409 | 1946 | now | |
| S-410 | 1955 | 1975 → 343 (part) | |
| S-411 | 1946 | now | |
| S-412 | 1995 | now | numbered as spur of 411 |
| S-412 | 1947 | 1975 → US 12 |
west from Lolo; became P-93 in 1976 |
| S-413 | 1948 | now | |
| S-414 | 1948 | 1975 | south from St. Phillip |
| S-415 | 1950 | 1975 → 384 (part) | |
| S-416 | 1950 | now | |
| S-417 | 1950 | now | |
| S-418 | 2000 | now | numbered as spur of 416 |
| S-418 | 1951 | 1975 | southwest from Wyola |
| S-419 | 1951 | now | |
| S-420 | 1951 | now | |
| S-421 | 1951 | now | |
| S-422 | 1951 | now | |
| S-423 | 1951 | 1975 | German Gulch Road, west of Butte |
| S-424 | 1951 | now | |
| S-425 | 1951 | 1975 | southwest from Fishtail |
| S-426 | 1951 | now | |
| S-427 | 1951 | now | |
| S-428 | 2001 | 2001 | a bit of the I-90 south frontage road east from Wise Lane, Billings only appears in 2001 log (which erroneously says it comes from 1952), but the 1999 log is missing |
| S-428 | 1952 | 1977 → 297 (part) |
east from Judith Gap |
| S-429 | 1952 | 2001 | I-90 south frontage road, Wise Lane, and 40th Street West, Elysian Road to Rimrock Road, Billings mostly removed in 1997-2001 |
| S-430 | 1987 | now | why this number? |
| S-430 | 1955 | 1980 → FAU 8103 |
Reserve Street, Missoula; now US 93 |
| S-431 | 1955 | now | had been 222 in the 1940s |
| S-432 | 1955 | now | |
| S-433 | 1955 | 1975 | Wylie Drive, east of Helena |
| S-434 | 1955 | now | |
| S-435 | 1987 ← 434 (part) |
now | |
| S-435 | 1955 | 1975 | northwest from Augusta |
| S-436 | 1955 | 1975 | northeast from Zurich |
| S-437 | 1956 | now | |
| S-438 | 1955 | now | |
| S-439 | never? | never? | was this number skipped? |
| S-440 | 1956 | 1975 | Beef Trail Road and Little Basin Creek Road, southwest from Butte |
| S-441 | 1956 | now | |
| S-442 | never? | never? | was this number skipped? |
| S-443 | never? | never? | was this number skipped? |
| S-444 | 1956 | now | |
| S-445 | 1956 | 1975 | northwest from Browning |
| S-446 | 1956 | now | had been 316 in the 1940s |
| S-447 | 1956 | now | |
| S-448 | 1955 | now | |
| S-449 | 1955 | now | |
| S-450 | 1955 | 1975 | south from Kremlin |
| S-451 | 1988 ← US 87 (part) |
now | why this number? |
| S-451 | 1955 | 1960 → 448 (part) |
west from Box Elder |
| S-452 | 1955 | 1975 | southeast from Havre |
| S-453 | 1956 | now | |
| S-454 | 1956 | now | |
| S-455 | 1956 | 1956 → 310 (part) |
northwest from Custer |
| S-456 | 1956 | 1975 | Lodgepole Road, west of Whitefish |
| S-457 | 1988 ← P-74 |
now | why this number? |
| S-457 | 1956 | 1970 → 366 (part) |
across Tiber Dam |
| S-458 | 1956 | 1975 → 345 (part) |
19th Avenue, south from Bozeman |
| S-459 | 1956 | 1993 | 13th Street, 10th Avenue South to 226, south from Great Falls |
| S-460 | 1956 | 1975 | south from Gold Creek |
| S-461 | 1956 | 1975 → 135 | |
| S-462 | 1956 | now | |
| S-463 | 1957 | now | |
| S-464 | 1957 | now | |
| S-465 | 1956 | 1975 | north from Van Norman |
| S-466 | 1956 | now | disappeared in 1976, but returned in 1978 |
| S-467 | 1957 | now | |
| S-468 | 1957 | 1958 → 254 (part) |
northwest from Richey |
| S-469 | 1957 | 1985 | north of Fairview |
| S-470 | 1957 | now | |
| S-471 | 1957 | now | had been 4 until 1938-1939 |
| S-472 | 1993 | now | why this number? |
| S-472 | 1957 | 1975 | northeast from Sula |
| S-473 | 1957 | now | |
| S-474 | 1957 | now | |
| S-475 | 1957 | 1975 → 295 (part) |
east of Livingston |
| S-476 | 1957 | 1975 | southeast from Pray |
| S-477 | 1957 | 1975 | west from Red Lodge |
| S-478 | 1957 | now | |
| S-479 | 1957 | 1975 | north of Big Timber |
| S-480 | 1957 | now | |
| S-481 | 1957 | 1975 | Old Highway 282, southeast of Helena (was this actually part of 282?) |
| S-482 | 1958 | now | |
| S-483 | 1958 | 1975 → 213 (part) | |
| S-484 | 1958 | now | |
| S-485 | 1959 | 1975 | southwest of Broadus |
| S-486 | 1958 | now | |
| S-487 | 1958 | now | |
| S-488 | 1959 | 1981 | east of Sidney |
| S-489 | 1959 | now | disappeared in 1976, but returned in 1985 |
| S-490 | 1959 | 1975 | east from Conner |
| S-491 | never? | never? | was this number skipped? |
| S-492 | 1959 | 1975 | became 326 in 1990 |
| S-493 | 1959 | now | |
| S-494 | 1959 | now | |
| S-495 | 1959 | 1975 | 25th Avenue, Rainbow Dam Road, and Morony Dam Road, Old Havre Highway to US 87, north of Great Falls |
| S-496 | 1959 | 1975 | northeast of Culbertson |
| S-497 | 1959 | 1975 | northwest from Harlowton |
| S-498 | 1959 | 1974 → FAU 5205 |
River Drive and 57th Street, 9th Street to 10th Avenue South, Great Falls (mileage is off - 4.5 may be a typo) |
| S-499 | 1959 | 1975 → US 287 (part) |
had been part of 287 until 1959 Yellowstone earthquake signed as part of US 287 from 1965; became P-87 in 1976 |
| S-500 | 1960 | now | |
| S-501 | 1960 | 1975 | south of Grantsdale |
| S-502 | 1960 | 1975 | 56th Street, I-90 to King Avenue, west of Billings |
| S-503 | 1960 | now | |
| S-504 | 1960 | now | |
| S-505 | 1960 | 1980 → 426 (part) | |
| S-506 | 1961 | 1975 | became 260 in 1986 |
| S-507 | 1961 | now | |
| S-508 | 1961 | now | |
| S-509 | 1961 | now | |
| S-510 | 1961 | 1999 | east from Brockway 1999 log not available, but it's on the 1999 map |
| S-511 | 1962 ← 13 (part) |
now | |
| S-512 | 1962 | now | |
| S-513 | 1962 | now | |
| S-514 | 1962 | 1975 | north from Poplar |
| S-515 | 1991 | 2001 | southwest from Plentywood on the 2001 map but not the 2001 log why this number? |
| S-515 | 1961 | 1975 | became 573 in 2001 |
| S-516 | 1961 | now | |
| S-517 | 1961 | now | |
| S-518 | 1961 | now | |
| S-519 | 1962 | 1978 | northeast of Roundup |
| S-520 | 1962 ← US 10 (part) |
1975 | west from Cyr |
| S-521 | 1962 | 1972 | Northwest Bypass, Great Falls became part of FAP 3 at first, but in 1974 it became FAU 5206 |
| S-522 | 1962 | now | |
| S-523 | 1963 ← US 2 (part) |
1975 → 241 (part) |
through Harlem |
| S-524 | 1962 | 1975 | Rocky Point Road, northwest of Polson |
| S-525 | 1962 | 1975 | Finley Point Road, northeast of Polson |
| S-526 | 1963 | 1975 | north from Logan |
| S-527 | 1963 | 1975 | southwest of Cameron |
| S-528 | 1963 | now | disappeared in 1976, but returned in 1998 |
| S-529 | 1963 | now | |
| S-530 | 1963 | 1975 | east from Ronan |
| S-531 | 1963 | now | |
| S-532 | 1964 | now | |
| S-533 | 1965 | 2005? | Pattee Canyon Drive and Deer Creek Road, east of Missoula in 2005 log but not 2005 traffic counts (it is in the 2004 traffic counts) |
| S-534 | 1964 | now | had been 217 in the 1940s |
| S-535 | 1964 | 1974 → FAU 1004, FAU 1018 |
Grand Avenue and 6th Avenue North, Shiloh Road to US 87, Billings |
| S-536 | 1964 | 1993 | Griffin Drive, Bozeman |
| S-537 | 1965 | now | |
| S-538 | 1965 | 1974 → FAU 1810 |
Grand Avenue, Harrison Avenue to Continental Drive, Butte |
| S-539 | 1965 | 1975 | Hauser Street, east of Anaconda |
| S-540 | 1966 | now | |
| S-541 | 1966 | now | |
| S-542 | 1967 | 1975 | became 572 in 2001 |
| S-543 | 1967 | now | |
| S-544 | 1968 | now | |
| S-545 | 1968 | 1974 → FAU 1203 |
Lincoln Street and 11th/10th Avenue, 19th Avenue to Main Street, Bozeman |
| S-546 | 1968 | 1975 → 322 (part) |
northeast of Ekalaka |
| S-547 | 1969 | now | |
| S-548 | 1969 | now | |
| S-549 | 1970 | 1993 | east from Whitehall |
| S-550 | never? | never? | was this number skipped? |
| S-551 | 1971 | now | |
| S-552 | 1973 | now | |
| S-553 | never? | never? | was this number skipped? |
| S-554 | 1971 | 1975 | northeast from Winston |
| S-555 | never? | never? | was this number skipped? |
| S-556 | 1971 | now | |
| S-557 | 1971 | 1974 → FAU 5221 |
Giant Springs Road, River Drive to Giant Springs, Great Falls |
| S-558 | 1972 | 1974 → FAU 5204 |
Smelter Avenue and River Road, 10th Street to 15th Street, Great Falls |
| S-559 | 1973 | now | |
| S-560 | never? | never? | was this number skipped? |
| S-561 | never? | never? | was this number skipped? |
| S-562 | never? | never? | was this number skipped? |
| S-563 | 1975 | 2001 | northwest from Springdale not in 2001 log, but on maps through 2002 |
| S-564 | 1975 | now | |
| S-565 | 1975 | now | |
| S-566 | 1975 | now | |
| S-567 | 1994 ← 508 (part) |
now | |
| S-568 | 1976 | now | |
| S-569 | 2001 | now | had been 274 until 1985-1987 |
| S-569 | 1976 | 1981 | Johnson Lane, east of Billings |
| S-570 | 2001? | 2012? | first appears in the 2001 log, which claims it was created in 1993; first map is 2002; became part of S-412 when the bridge opened? |
| S-571 | 2001 | now | had been 362 until 1975-1976 |
| S-572 | 2001 | now | had been 542 until 1975-1976 |
| S-573 | 2001 | now | had been 515 until 1975-1976 |
| S-574 | 2006 | now | creation date from 2011 log (p. 237) |
| MT 789 | 1954 | 1971 | completely overlapped other routes |