Wikipedia:WikiProject U.S. Roads/Idaho/highway numbers

All unnumbered highways received a number in 1953 (minutes p. 63). A partial 1923 map is at and a full 1925 map is at.


 * SH-1
 * US-95 Copeland to Canada Porthill
 * 1959: same
 * Copeland-Porthill Road


 * US-2
 * Washington Newport to Montana
 * 1959: same
 * ? Washington-Sandpoint, Kootenai Highway Bonners Ferry-Montana


 * SH-3
 * US-12 to I-90
 * 1959: US-95A to I-90; rest was SH-42, SH-7, SH-8, SH-43, US-95A


 * SH-4
 * I-90 Wallace to Burke
 * 1959: same


 * SH-5
 * US-95 Plummer to SH-3 Saint Maries
 * 1959: same


 * SH-6
 * Washington to SH-3 Santa
 * 1959: Washington to US-95 Potlatch; rest was US-95A


 * SH-7
 * Clearwater/Lewis County line to US-12 Orofino
 * 1959: US-95 Grangeville to US-95A Harvard; now N/A, SH-162, SH-62, N/A, SH-7, N/A, SH-3, SH-9
 * Grangeville-Harvard Highway


 * SH-8
 * Washington Moscow to Elk River
 * 1959: Washington Moscow to SH-43 Bovill; rest was SH-43
 * Deary-Bovill Road


 * SH-9
 * SH-8 Deary to SH-6 Harvard
 * 1959: N/A; was SH-7


 * Former SH-9
 * 1959: US-95 Spalding to Montana Lolo Pass; now US-12
 * Lewis & Clark Highway


 * Former US-10
 * 1959: Washington to Montana Lookout Pass; now I-90
 * Coeur d'Alene-Yellowstone Trail (formerly North Pacific Highway) Coeur d'Alene-Montana


 * Former US-10A
 * 1959: US-10 Coeur d'Alene to Montana; now US-95, SH-200
 * Clark Fork Highway


 * SH-11
 * US-12 Greer to Headquarters
 * 1959: same
 * Clearwater Highway


 * US-12
 * Washington Lewiston to Montana Lolo Pass
 * 1959: N/A; was US-410, US-95, SH-9


 * Former SH-12
 * 1959: US-95 Craigmont to SH-9 Kamiah; now SH-62, SH-64
 * Nez Perce Highway


 * SH-13
 * US-95 Grangeville to US-12 Kooskia
 * 1959: same


 * SH-14
 * SH-13 Harpster to Elk City
 * 1959: same
 * Elk City Highway


 * I-15
 * Utah to Montana Monida Pass
 * 1959: N/A; was US-191, US-91


 * Former SH-15
 * 1959: SH-44 Eagle to US-95 New Meadows; now SH-55
 * Payette Highway


 * SH-16
 * SH-44 Star to SH-52 Emmett
 * 1959: same


 * Former SH-17
 * 1959: SH-15 Banks to Crouch; now N/A
 * Banks-Crouch Road


 * Former SH-18
 * 1959: Oregon to US-95 Parma; now N/A


 * SH-19
 * Oregon to I-84B Caldwell
 * 1959: same


 * US-20
 * Oregon to Montana Targhee Pass
 * 1959: same; was SH-68, SH-23 Mountain Home to Carey (used current US-26)


 * Former US-20A
 * 1959: US-20 Sugar City to Wyoming; now SH-33


 * SH-21
 * I-84 Boise to SH-75 Stanley
 * 1959: same
 * Boise-Stanley Highway (earlier Arrowrock Highway)


 * SH-22
 * SH-33 Howe to I-15 Dubois
 * 1959: US-20 Arco to I-15 Dubois; now SH-33, SH-22
 * Idaho Central Highway


 * Former SH-23
 * 1959: US-26 Carey to US-93 Bellevue; now US-20, N/A
 * Bellevue-Gannett Highway


 * SH-24
 * I-84 Heyburn to US-93 Shoshone
 * Lincoln-Minidoka County line to Minidoka removed in 1958 - reverted to state in 1959
 * 1959: same


 * SH-25
 * I-84 Jerome to I-84 Rupert
 * 1959: US-30 Bliss to US-30N Rupert; now I-84, SH-25
 * North Side Highway


 * US-26
 * Oregon to Wyoming Alpine
 * 1959: same


 * Former SH-26
 * US-93 to US-30 Twin Falls; now SH-74


 * SH-27
 * Oakley to SH-25 Paul
 * 1959: same


 * SH-28
 * SH-33 Terreton to US-93 Salmon
 * 1956 (minutes p. 38): US-91 to US-93 Salmon; now SH-33, SH-28
 * 1959: same
 * Lemhi Highway


 * SH-29
 * SH-28 Leadore to Montana Bannock Pass
 * 1959: same


 * Former SH-29
 * Until ca. 1951: US-20 Idaho Falls to Wyoming Alpine; now US-26


 * US-30
 * Oregon Fruitland to Wyoming Border
 * 1959: Oregon Fruitland to US-30N/US-30S Heyburn; rest was US-30N
 * Old Oregon Trail Highway


 * Former US-30N
 * 1959: Oregon Weiser to US-30 Fruitland; now US-95 Spur
 * 1959: US-30/US-30S Heyburn to Wyoming Border; now US-30
 * Old Oregon Trail Highway


 * Former US-30S
 * 1959: US-30/US-30N Heyburn to Utah Strevell; now SH-81, N/A


 * SH-31
 * US-26 Swan Valley to SH-33 Victor
 * 1959: same


 * SH-32
 * SH-33 Tetonia to SH-47 Ashton
 * 1959: same
 * Ashton-Drummond-Tetonia Road


 * SH-33
 * US-20/US-26 Arco to Wyoming
 * 1959: US-20 Sugar City to Wyoming (also overlapped by US-20A); rest was SH-22, SH-88


 * SH-34
 * US-91 Preston to Wyoming Freedom
 * Until 1951: US-91 Preston to Wyoming Freedom; now SH-34
 * 1959: Utah to Wyoming Freedom; now N/A, SH-34
 * Preston-Fairview Highway (1951)


 * Former SH-35
 * 1959: Utah to US-91 Downey; now N/A, SH-36, N/A
 * Dayton-Red Rock Road


 * SH-36
 * I-15 Malad to US-89 Paris
 * 1959: N/A; was N/A, SH-35, SH-86, N/A


 * Former SH-36
 * 1959: ???


 * SH-37
 * Oneida/Power County line to I-86 American Falls
 * 1959: US-191 Malad to US-30N American Falls; now SH-38, N/A, SH-37


 * SH-38
 * I-15 Malad to Holbrook
 * 1959: N/A; was SH-37


 * Former SH-38
 * Until 1955: SH-37 Holbrook to US-30N Pocatello
 * 1959: SH-37 Holbrook to Power/Bannock County line; now N/A


 * SH-39
 * American Falls to US-26 Blackfoot
 * 1959: same


 * SH-40
 * I-15 to US-91 Downey
 * 1959: N/A; was N/A


 * Former SH-40
 * 1959: ???


 * SH-41
 * I-90 Post Falls to US-2 Newport
 * 1959: same


 * Former SH-42
 * 1959: US-95 Spalding to SH-7 Kendrick; now SH-3


 * SH-43
 * US-26 Beeches Corner to US-20 Ucon
 * 1959: N/A; was N/A


 * Former SH-43
 * 1959: Elk River to US-95A Santa; now SH-8, SH-3


 * SH-44
 * I-84 Caldwell to US-20/US-26 Garden City
 * 1959: same
 * Boise Valley Highway Caldwell-Boise


 * SH-45
 * SH-78 to I-84B Nampa
 * 1959: Murphy to US-30 Nampa; now SH-78, SH-45


 * SH-46
 * I-84 Wendell to US-20 Fairfield
 * 1959: same
 * Gooding-Fairfield Road


 * SH-47
 * US-20 Ashton to Bear Gulch in Targhee National Forest
 * Created in 1957 from old US-20/US-191; removed in 1957 and restored in 1958??
 * 1959: same


 * Former SH-47
 * Until 1951 (or 1957??): Rock Creek Road, US-20 Ashton to Wyoming
 * 1956 (minutes p. 39): US-20 Ashton to Wyoming


 * SH-48
 * I-15 Roberts to US-26B Ririe
 * 1959: same


 * Former SH-49
 * Early: Oregon to US-30 Nyssa
 * Nyssa Bridge Spur


 * Until 1957: US-191 Idaho Falls to SH-48 Menan
 * 1959: north of Idaho Falls to SH-48 Menan; now N/A


 * SH-50
 * US-30 Twin Falls to SH-25 Eden
 * 1959: same


 * SH-51
 * Nevada to I-84B Mountain Home
 * 1959: same
 * Bruneau-Duck Valley Highway


 * SH-52
 * Oregon Payette to SH-55 Horseshoe Bend
 * Until 1950: US-30N Payette to SH-15 Horseshoe Bend
 * 1959: same
 * Payette Spur of the Old Oregon Trail Highway (1950), Payette-Emmett Highway, Emmett-New Plymouth Highway, Emmett Branch of the Payette Highway Emmett-Horseshoe Bend


 * Former SH-52A
 * Existed by 1955 (minutes p. 90)
 * 1959: SH-52 Emmett west; now N/A
 * Payette-Emmett Highway


 * SH-53
 * Washington to US-95
 * 1959: same


 * SH-54
 * SH-41 to Bayview
 * 1959: same


 * SH-55
 * US-95 Marsing to US-95 New Meadows
 * 1959: N/A; was SH-72, SH-69, SH-15


 * Former SH-55
 * Until 1955: US-2 Colburn to US-10A Culver
 * 1959: N/A


 * Former SH-56
 * Until 1955: US-95 Sagle to Midas
 * 1959: N/A


 * SH-57
 * US-2 Priest River to Nordman
 * 1959: same
 * Priest River Road Priest River-Nordman


 * SH-58
 * Washington to US-95
 * 1959: same


 * Former SH-59
 * 1959: ???


 * SH-60
 * Washington to US-95
 * Created in 1959


 * Former SH-60
 * 1959: ???


 * SH-61
 * Wyoming to US-89 Geneva
 * Existed by 1955 (minutes p. 110)
 * 1959: same


 * SH-62
 * US-95B Craigmont to SH-64/SH-162 Nezperce
 * 1959: N/A; was SH-12


 * Former SH-62
 * 1951: created
 * 1959: SH-7 Greencreek to SH-9 Kamiah; now SH-162
 * Kamiah-Green Creek Highway (1951)


 * Former SH-63
 * 1959: ???


 * SH-64
 * SH-62/SH-162 Nezperce to SH-162 Kamiah
 * 1959: N/A; was SH-12


 * Former SH-64
 * 1959: ???


 * Former SH-65
 * 1959: ???


 * SH-66
 * Washington to US-95
 * 1959: same


 * SH-67
 * SH-78 Grand View to SH-51 Mountain Home
 * Created 1954
 * 1959: Mountain Home AFB to SH-51 Mountain Home; rest was N/A


 * Former SH-68
 * 194x: part of SH-22
 * existed by 1954 (minutes p. 38)
 * 1959: US-30 Mountain Home to SH-23 Gannett; now US-20
 * Idaho Central Highway?


 * SH-69
 * Kuna to I-84 Meridian
 * Existed by 1954 (minutes p. 89)
 * 1959: Kuna to SH-44 Eagle; now SH-69, SH-55


 * Former SH-70
 * 1959: Eaton to US-30N Weiser; now N/A


 * SH-71
 * Oregon to US-95 Cambridge
 * Created in 1957
 * 1959: same


 * SH-72
 * US-30 to SH-52
 * 1959: N/A; was SH-52?


 * Former SH-72
 * existed by 1954 (minutes p. 32)
 * 1959: US-95 Marsing to US-30 Nampa; now SH-55


 * Former SH-73
 * Until 1953: Buhl-Castleford Highway, US-30 Buhl to Castleford
 * 1959: N/A


 * SH-74
 * US-93 to US-30 Twin Falls
 * 1954 (minutes p. 29): still SH-26
 * 1955 (minutes p. 132): SH-74
 * 1959: same


 * SH-75
 * US-26/US-93 Shoshone to US-93 Challis
 * 1959: N/A; was US-93


 * Former SH-75
 * 1959: US-93 Ketchum to Sun Valley; now N/A
 * Sun Valley Spur (1954 minutes p. 51; doesn't call it SH-75)


 * Former SH-76
 * Until 1954: Richfield north
 * 1959: N/A


 * SH-77
 * SH-81 Malta to I-84 Rupert
 * Existed by 1955 (minutes p. 132)
 * 1959: Albion to US-30N Rupert; rest was N/A


 * SH-78
 * SH-55 Marsing to I-84B Hammett
 * 1959: N/A; was N/A


 * Former SH-78
 * 1959: ???


 * SH-79
 * I-84 to Jerome
 * Existed by 1955 (minutes p. 132)
 * Until 1957: US-93 Twin Falls to US-93 south of Shoshone
 * 1959: US-93 Twin Falls to SH-25 Jerome; now I-84, SH-79
 * Jerome Branch of Sawtooth Park Highway


 * Former SH-80
 * Existed by 1955 (minutes p. 104)
 * 1959: SH-48 Menan to US-20 Lorenzo; now N/A


 * SH-81
 * SH-77 Malta to US-30/I-84B Burley
 * 1959: N/A; was US-30S


 * Former SH-81
 * 1959: ???


 * Former SH-82
 * 1959: ???


 * Former SH-83
 * 1959: ???


 * I-84
 * Oregon to Utah
 * 1959: N/A; was US-30, SH-25, US-30S


 * Former SH-84
 * Created 1957
 * 1959: US-20 Macks Inn to Big Springs; now N/A


 * Former SH-85
 * 1959: ???


 * I-86
 * I-84 to I-15 Pocatello
 * 1959: was US-30N


 * Former SH-86
 * Existed by 1954 (minutes p. 90): SH-35 Dayton to US-91 Preston; now SH-36
 * 1959: shown but unlabeled


 * SH-87
 * US-20 to Montana
 * 1959: N/A; was N/A


 * Former SH-87
 * 1959: ???


 * Former SH-88
 * Created in 1958
 * 1959: US-20 Arco to US-20 Rexburg; now SH-33


 * US-89
 * Utah Fish Haven to Wyoming Geneva
 * 1959: same


 * I-90
 * Washington to Montana
 * 1959: was US-10


 * US-91
 * Utah Franklin to I-15B Idaho Falls
 * 1959: Utah Franklin to Montana Monida Pass; now US-91, I-15
 * Redrock-Preston Highway, Idaho-Montana Highway


 * US-93
 * Nevada to Montana Lost Trail Pass
 * 1959: same; used SH-75 Shoshone to Challis and was US-93A


 * Former US-93A
 * 1959: US-93 Shoshone to US-93 Challis; now US-93


 * US-95
 * Oregon to Canada
 * 1959: same
 * North and South Highway Weiser-Canada


 * Former US-95A
 * 1959: US-95 Potlatch to US-95 Coeur d'Alene; now SH-6, SH-3, SH-97


 * Former SH-96
 * Created in 1959: US-20 north of Macks Inn to Montana Reynolds Pass; now SH-87


 * SH-97
 * SH-3 to I-90 Coeur d'Alene
 * 1959: N/A; was US-95A


 * SH-99
 * SH-3 Kendrick to SH-8 Troy
 * 1959: N/A; was N/A


 * SH-128
 * Washington Lewiston to US-12 Lewiston
 * 1959: N/A; was N/A


 * SH-162
 * SH-62/SH-64 Nezperce to US-12 Kamiah
 * 1959: N/A; was SH-12


 * I-184
 * I-84 Boise to US-20 Spur/US-26 Spur Boise
 * 1959: N/A; was N/A


 * Former US-191
 * 1959: Utah to Montana Targhee Pass; now I-15, US-20
 * Yellowstone Park Highway


 * SH-200
 * US-95 Sandpoint to Montana
 * 1959: N/A; was US-10A


 * Former US-410
 * 1959: Oregon Lewiston to US-95 Lewiston; now US-12


 * Unknown
 * Until 1950: portion of Idaho Central Highway, US-91 Spencer to US-20 Trude
 * Until 1952: Thain Road, US-410 Lewiston to Lewiston Orchards
 * Until 1952: Triumph Mine Road, US-93 Gimlet to Triumph
 * Until 1953: Ammon Spur, Idaho Falls to Ammon