State highways in the U.S. state of Iowa are owned and maintained by the Iowa Department of Transportation.
Highway markers from different years | |
| Highway names | |
|---|---|
| Interstates | Interstate nn (I-nn) |
| US Highways | U.S. Highway nn (US nn) |
| State | Iowa nn |
| System links | |
State highways
edit| Number | Length (mi)[1][2] | Length (km) | Southern or western terminus | Northern or eastern terminus | Formed | Removed | Notes | |
|---|---|---|---|---|---|---|---|---|
| 236[3] | 380 | Missouri state line near Lamoni | Minnesota state line near Northwood | 1920 | 1926 | Jefferson Highway through Iowa; replaced by US 65 and US 69 | ||
| 119.268 | 191.943 | Iowa 2 south of Keosauqua | US 151 south of Anamosa | 1926 | current | |||
| 233.80[4] | 376.26 | US 6 near Lewis | IL 2 at Muscatine | 1920 | 1939 | Renumbered Iowa 92 (renumbering approved 1938) | ||
| 251.376 | 404.550 | N-2 at Nebraska City, Neb. | US 61 at Fort Madison | 1941 | current | Formerly Iowa 3 | ||
| 267.07[4] | 429.81 | N-2 at Nebraska City, Neb. | IL 9 at Fort Madison | 1920 | 1941 | Renumbered Iowa 2 | ||
| 323.102 | 519.982 | SD 50 near Westfield | Northwest Arterial at Dubuque | 1945 | current | Replaced part of Iowa 5, all of Iowa 221, and part of Iowa 10 | ||
| 29.70[5] | 47.80 | US 59 / Iowa 141 at Denison | Iowa 175 at Odebolt | 1920 | 1968 | Renumbered Iowa 39 | ||
| 146.343 | 235.516 | Iowa 44 in Panora | MN 4 near Estherville | 1969 | current | Formerly Iowa 17 | ||
| 77.64[5] | 124.95 | Iowa 3 near Aurelia | US 169 at Fort Dodge | 1920 | 1968 | Renumbered Iowa 7 | ||
| 103.540 | 166.631 | Route 5 south of Cincinnati | I-35 near West Des Moines | 1969 | current | Formerly portion of Iowa 60 | ||
| 369[3] | 594 | Nebraska state line at Council Bluffs | Illinois state line at Clinton | 1920 | 1926 | Lincoln Highway through Iowa; replaced by US 30 | ||
| 104 | 167 | Route 5 near Cincinnati | US 32 in Des Moines | 1926 | 1931 | Formerly No. 17 and No. 59; became part of Iowa 60 when US 6 extended into Iowa | ||
| 140.69[4] | 226.42 | US 6 at Council Bluffs | City US 6 in Des Moines | 1920 | 1939 | Replaced by an extended Iowa 64 | ||
| 0.47[6] | 0.76 | Iowa 99 in Oakville | Oakville | 1955 | 1957 | Renumbered Iowa 407; spur route | ||
| 24.18[5] | 38.91 | I-29 / US 77 in Sioux City | Iowa 3 near Brunsville | 1957 | 1968 | Formerly Iowa 29; portion became Iowa 985 | ||
| 73.661 | 118.546 | Iowa 3 near Aurelia | US 169 at Fort Dodge | 1969 | current | Formerly Iowa 5 | ||
| 283[3] | 455 | No. 6 in Council Bluffs | Illinois state line at Burlington | 1920 | 1926 | Replaced by US 34 | ||
| 13.961 | 22.468 | US 63 in Traer | US 218 near Garrison | 1926 | current | |||
| 295.088 | 474.898 | SD 42 near Larchwood | WIS 82 at Lansing | 1920 | current | |||
| 104.512 | 168.196 | SD 46 near Hawarden | Iowa 4 at Havelock | 1920 | current | |||
| 96.60[4] | 155.46 | US 151 / Iowa 64 in Cedar Rapids | US 52 / Iowa 24 in Calmar | 1920 | 1941 | Replaced by Iowa 150, which was proposed to become part of US 150 | ||
| 46.274 | 74.471 | US 20 / US 75 at Sioux City | Iowa 10 in Hawarden | 1920 | current | Signed as US 20 Bus through Sioux City | ||
| 85.235 | 137.172 | US 30 / US 151 near Bertram | US 52 near Froelich | 1920 | current | |||
| 187.838 | 302.296 | Iowa 2 at Corydon | US 18 / US 218 Bus in Charles City | 1920 | current | |||
| 111 | 179 | US 30 in Ames | Minnesota state line near Lake Mills | 1920 | 1935 | Replaced by US 69 | ||
| 14.92[5] | 24.01 | Iowa 137 at Eddyville | US 63 in Ottumwa | 1937 | 1968 | Renumbered Iowa 23 | ||
| 4.655 | 7.491 | Route 15 south of Milton | Iowa 2 at Milton | 1969 | 2003 | Formerly Iowa 23 | ||
| 63.578 | 102.319 | Iowa 3 near Pocahontas | MN 15 near Armstrong | 1969 | current | Formerly Iowa 44 | ||
| 239 | 385 | Missouri state line near Redding | Minnesota state line near Ledyard | 1920 | 1930 | Replaced by US 169 | ||
| 65.488 | 105.393 | US 34 near Agency | US 61 at Wever | 1930 | current | |||
| 147.48[5] | 237.35 | Iowa 64 in Panora | MN 4 near Estherville | 1920 | 1968 | Renumbered Iowa 4 | ||
| 102.789 | 165.423 | Iowa 141 at Granger | US 18 near Wesley | 1969 | current | Formerly portion of Iowa 60 | ||
| 148 | 238 | Missouri state line at Braddyville | No. 23 at Sac City | 1920 | 1926 | Replaced by US 71 | ||
| 302 | 486 | South Dakota state line near Inwood | Wisconsin state line at Lansing | 1920 | 1926 | East end truncated to US 75 for a month in 1926; replaced by US 18 | ||
| 2.44[6] | 3.93 | Backbone State Park | Iowa 3 / Iowa 13 near Strawberry Point | 1927 | 1957 | Renumbered Iowa 410 | ||
| 324[3] | 521 | Illinois state line at Keokuk | Minnesota state line near Burr Oak | 1920 | 1926 | Replaced by US 61 and US 55 | ||
| 115 | 185 | Minnesota state line near Allendorf | Iowa 141 near Denison | 1920 | 1934 | Replaced by Iowa 73 (proposed US 73) | ||
| 97.152 | 156.351 | Iowa 149 near Hedrick | US 20 / Iowa 27 at Waterloo | 1934 | current | Formerly ended at Iowa 92; extended south in 1980 | ||
| 34[3] | 55 | No. 5 at Le Mars | Minnesota state line north of Rock Rapids | 1920 | 1926 | Replaced by US 75 | ||
| 97.905 | 157.563 | Iowa 21 near Thornburg | US 61 at Davenport | 1926 | current | |||
| 130[3] | 210 | South Dakota state line at Sioux City | No. 16 at Fort Dodge | 1920 | 1926 | Replaced by US 20 | ||
| 4.78[5] | 7.69 | Route 15 south of Milton | Iowa 2 at Milton | 1926 | 1968 | Formerly part of No. 11; renumbered Iowa 15 | ||
| 14.316 | 23.039 | US 63 in Ottumwa | Iowa 137 at Eddyville | 1969 | 1997 | Formerly Iowa 15; partially replaced by US 63 | ||
| 16.022 | 25.785 | Iowa 92 at Oskaloosa | Iowa 149 near Fremont | 1997 | current | Formerly US 63 | ||
| 127 | 204 | US 71 near Lyman | US 63 in Oskaloosa | 1920 | 1927 | Replaced by an extended Iowa 2 | ||
| 27.546 | 44.331 | US 18 / US 63 in New Hampton | US 52 / Iowa 150 in Calmar | 1928 | current | |||
| 20 | 32 | No. 15 / No. 24 at Winterset | No. 2 / No. 17 at Adel | 1920 | 1926 | Replaced by relocated Iowa 16 | ||
| 103.419 | 166.437 | Iowa 2 near Benton | US 30 near Scranton | 1926 | current | Continued south to the Missouri state line until 1978, and to Blockton until 1980 | ||
| 10 | 16 | US 18 near Rock Valley | US 18 near Rock Valley | 1920 | 1930 | Replaced by relocated US 18 (portions were cancelled in exchange for relocated US 18) | ||
| 9.52[5] | 15.32 | US 18 in Inwood | Iowa 9 near Larchwood | 1930 | 1968 | Renumbered Iowa 182 | ||
| 11.370 | 18.298 | Iowa 9 in Lansing | MN 26 at New Albin | 1969 | current | Formerly Iowa 182 | ||
| 21.2 | 34.1 | Iowa 12 in Akron | US 75 in Le Mars | 1920 | 1929 | Replaced by an extended Iowa 5 | ||
| 11 | 18 | Nebraska border | US 30 / US 75 in Missouri Valley | 1929 | 1930 | Renumbered Iowa 130 | ||
| 6.86[7] | 11.04 | Alvord | US 75 near Rock Rapids | 1930 | 1980 | Spur route; originally from US 75 to George | ||
| 281.689 | 453.335 | Route 27 near Wayland, Mo. | I-35 at the Minnesota state line | 2001 | current | Avenue of the Saints | ||
| 72[3] | 116 | No. 6 / No. 11 in Cedar Rapids | No. 5 / No. 20 in Dubuque | 1920 | 1926 | Replaced by US 161 | ||
| 21.613 | 34.783 | Iowa 92 at Martensdale | I-35 / I-80 at Johnston | 1926 | current | Previously ended at Iowa 5; extended to US 6 in 1980, and to I-80 in 1991 | ||
| 22.06[6] | 35.50 | I-29 / US 77 in Sioux City | Iowa 3 near Brunsville | 1920 | 1957 | Renumbered Iowa 7 when I-29 was designated | ||
| 25 | 40 | No. 23 at Moville | No. 5 at Remsen | 1920 | 1926 | Renumbered Iowa 140 | ||
| 38.504 | 61.966 | US 59 near Quimby | Iowa 141 near Smithland | 1920 | current | |||
| 5 | 8.0 | No. 5 near Cleghorn | Cleghorn | 1920 | 1926 | Renumbered Iowa 145 | ||
| 7.68 | 12.36 | Iowa 9 near Spirit Lake | US 71 near Milford | 1934 | 1981 | extended and renumbered Iowa 86 to match Minnesota | ||
| 5.101[7] | 8.209 | US 20 at Dubuque | US 52 / Iowa 3 at Sageville | 1995 | 2021 | Turned over to Dubuque after the US 52 Southwest Arterial opened | ||
| 3.4 | 5.5 | Meriden | Iowa 5 | 1920 | 1930 | Became a county road (now L51) due to rerouting of Iowa 5 between Iowa 143 and Cherokee | ||
| 55.95[5] | 90.04 | US 75 at Le Mars | MN 60 at Bigelow, Minn. | 1930 | 1968 | Renumbered Iowa 60 | ||
| 68 | 109 | No. 4 at Denison | No. 12 at Sioux City | 1920 | 1926 | Renumbered Iowa 141 | ||
| 49.00[8] | 78.86 | Iowa 37 near Turin | US 71 near Odebolt | 1920 | 1948 | Replaced by an extended Iowa 175 | ||
| 0.23[6] | 0.37 | US 18 near Garner | Garner | 1954 | 1957 | Spur route; renumbered Iowa 409 when I-35 was designated | ||
| 2.983 | 4.801 | Wall Lake | US 71 near Wall Lake | 1920 | 2003 | Spur route; now County Roads M64 (north-south section) and D59 (east-west section) | ||
| 40.321 | 64.890 | Iowa 175 near Turin | US 59 near Earling | 1920 | current | Continued east to Irwin until 1982 | ||
| 98.941 | 159.230 | US 61 Bus / Iowa 92 in Muscatine | Iowa 3 near Edgewood | 1920 | current | |||
| 11.68[5] | 18.80 | US 30 near Logan | Iowa 64 / Iowa 191 at Portsmouth | 1920 | 1968 | Renumbered Iowa 44 | ||
| 24.321 | 39.141 | US 59 at Denison | Iowa 175 at Odebolt | 1969 | current | Formerly Iowa 4 | ||
| 262[3] | 422 | No. 20 in Keokuk | Minnesota state line near Mona | 1920 | 1926 | Replaced by US 161, US 20, US 30, and US 218; the entire route is now US 218 | ||
| 3.524 | 5.671 | Allerton | Iowa 2 near Corydon | 1926 | 2003 | Spur route; now County Road S26 | ||
| 1.827 | 2.940 | Malvern | US 34 near Malvern | 1920 | 2003 | Spur route; now County Road L63 | ||
| 4.18 | 6.73 | US 275 / Iowa 2 near Riverton | Riverton | 1920 | 1980 | Spur route; now County Road J46 | ||
| 1.75 | 2.82 | Ringsted | Iowa 15 near Ringsted | 1920 | 1980 | Spur route; now a local road and County Road A34 | ||
| 63.95[5] | 102.92 | Iowa 3 near Pocahontas | MN 15 near Armstrong | 1920 | 1968 | Renumbered Iowa 15 | ||
| 104.524 | 168.215 | US 30 near Logan | Iowa 141 at Grimes | 1969 | current | Formerly Iowa 39 and Iowa 64 | ||
| 1.324 | 2.131 | Manilla | Iowa 141 near Manilla | 1920 | 2003 | Spur route; now County Road M65 | ||
| 64.84[4] | 104.35 | US 59 near Denison | Iowa 17 (now Iowa 144) in Perry | 1920 | 1941 | Originally a double spur route; replaced by an extended Iowa 141 | ||
| 4.34 | 6.98 | Iowa 90 in Des Moines | Iowa 28 (now Army Post Road) in Des Moines | 1942 | 1950 | Now 9th Street, Mulberry Street, and 7th Street | ||
| 6.57[9] | 10.57 | Iowa 5 near Avon | Iowa 163 in Des Moines | 1953 | 1998 | Now city streets | ||
| 13 | 21 | Iowa 287 in Farnhamville | US 169 near Harcourt | 1920 | 1940 | Spur route; replaced by an extended Iowa 175 | ||
| 0.82 | 1.32 | Iowa 14 near Allison | Allison | 1941 | 1980 | Spur route; now 7th Street | ||
| 47.919 | 77.118 | US 59 at Shenandoah | US 6 near Lewis | 1920 | current | |||
| 27.228 | 43.819 | Iowa 2 in Bedford | US 34 in Adams County | 1920 | 2003 | Was originally a spur route from US 34 to Lenox; now County Roads N64, J23, N52, J35, and N44 (in order from US 34 to Iowa 2) | ||
| 7.135 | 11.483 | US 169 near Lehigh | Lehigh | 1920 | 2003 | Spur route; now County Road D43 | ||
| 11.007 | 17.714 | US 18 / US 52 at Postville | Iowa 9 near Waukon | 1920 | current | |||
| 7[10] | 11 | Elma | US 63 east of Elma | 1920 | 1934 | Spur route; renumbered Iowa 272 when US 52 extended into Iowa | ||
| 13 | 21 | No. 14 near Rockford | No. 19 near Nora Springs | 1920 | 1926 | Renumbered Iowa 147 to avoid conflict with US 53 (which became US 55 in the revised numbering plan; see below) | ||
| 3.04[8] | 4.89 | Iowa 3 near Clarksville | Clarksville | 1926 | 1949 | Formerly No. 55; became part of Iowa 188 | ||
| 1.43[11] | 2.30 | Gowrie | Iowa 175 near Gowrie | 1953 | 1969 | Spur route; now local roads (Market and 4th Streets) | ||
| 2.99 | 4.81 | Marble Rock | Iowa 14 in Floyd County | 1920 | 1980 | Spur route; now County Road B60 | ||
| 3 | 4.8 | No. 10 near Clarksville | Clarksville | 1920 | 1926 | Renumbered Iowa 53 to avoid conflict with US 55 | ||
| 4.506 | 7.252 | Seymour | Iowa 2 near Promise City | 1934 | 2003 | Spur route; now County Road S60 | ||
| 24.432 | 39.319 | Iowa 150 at West Union | Iowa 13 at Elkader | 1920 | current | |||
| 18.41[12] | 29.63 | Iowa 14 near Fern | Iowa 58 in Cedar Falls | 1920 | 1986 | Section from Iowa 58 to US 20 was deleted in 1980; removed after US 20 freeway was constructed | ||
| 43.765 | 70.433 | US 65 near Iowa Falls | US 218 / Iowa 27 / Iowa 58 at Cedar Falls | 1986 | current | Formerly US 20 | ||
| 12.030 | 19.360 | US 63 at Hudson | US 218 / Iowa 27 / Iowa 57 at Cedar Falls | 1920 | current | |||
| 197[10] | 317 | Minnesota state line | Iowa 5 at Albia | 1920 | 1934 | Replaced by US 63 and Iowa 137 | ||
| 233.24[5] | 375.36 | Route 5 south of Cincinnati | US 18 near Wesley | 1920 | 1968 | Renumbered Iowa 5 and Iowa 17 | ||
| 58.771 | 94.583 | US 75 at Le Mars | MN 60 at Bigelow, Minn. | 1969 | current | Formerly Iowa 33 | ||
| 73 | 117 | No. 28 at Anamosa | No. 6 in Lyons | 1920 | 1926 | Renumbered Iowa 117 and Iowa 136 | ||
| 19.633 | 31.596 | Iowa 64 at Maquoketa | US 52 in Bellevue | 1920 | current | |||
| 24 | 39 | No. 59 in New Sharon | No. 7 in Grinnell | 1920 | 1926 | Renumbered Iowa 146 | ||
| 32 | 51 | Iowa 163 at Prairie City | US 30 in Colo | 1920 | 1936 | Renumbered Iowa 117 | ||
| 64.355 | 103.569 | US 151 at Anamosa | US 52 / IL 64 at Savanna, Ill. | 1939 | current | Formerly Iowa 117 | ||
| 21 | 34 | No. 8 at Lucas | No. 1 south of Indianola | 1920 | 1926 | Renumbered Iowa 137 | ||
| 7 | 11 | Humeston | Iowa 3 near Humeston | 1920 | 1930 | Spur route; replaced by an extended Iowa 137 | ||
| 7.011 | 11.283 | Iowa 2 near Diagonal | Diagonal | 1930 | 2003 | Spur route; now County Road P33 | ||
| 6[10] | 9.7 | Seymour | Iowa 3 near Promise City | 1920 | 1934 | Spur route; renumbered Iowa 55 when US 67 extended into Iowa | ||
| 1.933 | 3.111 | Melrose | US 34 near Melrose | 1920 | 2003 | Spur route; now County Road S70 | ||
| 3 | 4.8 | No. 3 near Mystic | Mystic | 1920 | 1926 | Renumbered Iowa 138 | ||
| 8.20[5] | 13.20 | Macksburg | US 169 near Macksburg | 1920 | 1966 | Spur route; now County Road G41 | ||
| 23.954 | 38.550 | Iowa 92 at Columbus Junction | US 6 in West Liberty | 1969 | current | Formerly Iowa 76 | ||
| 3 | 4.8 | Moulton | No. 3 near Moulton | 1920 | 1926 | Renumbered Iowa 142 | ||
| 10.89[12] | 17.53 | US 69 west of Dows | I-35 east of Dows | 1920 | 1986 | Originally a spur route; extended east from Dows to I-35 in 1980 | ||
| 35.9 | 57.8 | Iowa 8 in Dysart | US 6 in Marengo | 1920 | 1934 | Renumbered Iowa 212 to avoid conflict with new Iowa 73, which was proposed to become part of US 73 | ||
| 225 | 362 | Missouri state line south of Shenandoah | Minnesota state line near Allendorf | 1934 | 1935 | Was proposed to become part of US 73; replaced by US 59 | ||
| 14.97[13] | 24.09 | Iowa 141 in Coon Rapids | Iowa 44 | 1936 | 1972 | Became County Road N46 | ||
| 38.27[4] | 61.59 | Iowa 38 in Tipton | US 61 in Davenport | 1920 | 1941 | Replaced by Iowa 150, which was proposed to become part of US 150 | ||
| 11.168 | 17.973 | US 151 in Cedar Rapids | Palo | 1943 | 1966 | Spur route; renumbred Iowa 94 when I-74 was designated | ||
| 2 | 3.2 | No. 5 near Marcus | Marcus | 1920 | 1926 | Renumbered Iowa 143 | ||
| 25.98[5] | 41.81 | Columbus City | US 6 in West Liberty | 1920 | 1968 | Renumbered Iowa 70 | ||
| 48.911 | 78.715 | US 18 near McGregor | MN 76 near Eitzen, Minn. | 1969 | current | Formerly portion of Iowa 13 | ||
| 2.685 | 4.321 | Iowa 92 near Keota | Keota | 1920 | 2003 | Spur route, continued south to Iowa 78 until 1980; now County Road W15 and a local road | ||
| 58.429 | 94.032 | Iowa 149 near Martinsburg | US 61 near Morning Sun | 1920 | current | |||
| 1.84 | 2.96 | Iowa 2 near Bonaparte | Bonaparte | 1920 | 1980 | Spur route; now County Road W40 | ||
| 5.637 | 9.072 | Geode State Park | US 34 in Middletown | 1980 | 2003 | Park access road; was a county road before commissioning and returned to a county road; initially known as County Road 79 until 2005 when it became J20 | ||
| 4.00[6] | 6.44 | US 34 near West Burlington | US 61 in Burlington | 1920 | 1957 | Spur route; renumbered Iowa 406 when I-80 was designated | ||
| 9.20[5] | 14.81 | Iowa 92 near West Chester | Iowa 22 at Wellman | 1920 | 1968 | Renumbered Iowa 114 | ||
| 2.215 | 3.565 | Route 81 near Farmington | Iowa 2 near Farmington | 1969 | current | Formerly Iowa 114 | ||
| 3.773 | 6.072 | Blairstown | US 30 near Blairstown | 1920 | 2003 | Spur route; now County Road V66 | ||
| 34.191 | 55.025 | US 59 in Avoca | Iowa 148 in Anita | 1920 | current | Continued west to Neola until 2003 | ||
| 6.09[8] | 9.80 | College Springs | US 71 near Shambaugh | 1920 | 1943 | Spur route; replaced by an extended Iowa 333 | ||
| 2.13 | 3.43 | Eastern Iowa Airport | I-380 near Cedar Rapids | 1943 | 1980 | Airport access road; now County Road E70 | ||
| 8.408 | 13.531 | Montezuma city limits | Iowa 21 near Deep River | 1920 | current | |||
| 4 | 6.4 | US 34 in Council Bluffs | Lake Manawa | 1920 | 1928 | Spur route; restored in 1931 as Iowa 241, later Iowa 192 | ||
| 3.7 | 6.0 | US 61 (now Sunnyside Avenue) in Burlington | US 61 (now Summer Street) in Burlington | 1929 | 1945 | Now Roosevelt Avenue and West Avenue | ||
| 0.47 | 0.76 | Fertile | Iowa 9 at Fertile | 1945 | 1980 | Spur route | ||
| 12.519 | 20.147 | US 71 near Milford | MN 86 near Spirit Lake | 1980 | current | |||
| 4.06[14] | 6.53 | US 69 west of Elkhart | Elkhart | 1920 | 1983 | Spur route | ||
| 37.65[4] | 60.59 | US 6 in Altoona | US 30 near Marshalltown | 1920 | 1939 | Originally a spur route; replaced by an extended Iowa 64 | ||
| 8.01 | 12.89 | US 61 / Iowa 2 in Fort Madison | Iowa 16 in Denmark | 1940 | 1980 | Originally a spur route | ||
| 25.87[4] | 41.63 | US 169 near Bouton | Iowa 64 in Johnston | 1920 | 1941 | Originally a spur route; replaced by an extended Iowa 141 | ||
| 7.69 | 12.38 | Iowa 141 near Woodward | Iowa 17 in Madrid | 1946 | 1980 | Replaced by an extended Iowa 210 | ||
| 40 | 64 | No. 17 near Bouton | No. 16 at Harcourt | 1920 | 1926 | Replaced by relocated Iowa 16 (now US 169) | ||
| 16 | 26 | Iowa 14 at Grundy Center | Iowa 59 near Voorhies | 1926 | 1932 | Formerly No. 58; became part of Iowa 58 again | ||
| 16.32[15] | 26.26 | I-80 in Dallas County | I-35 in Des Moines | 1932 | 1981 | Now County Road F90; section in Polk County maintained as unsigned Iowa 934 until 1989 | ||
| 2.69[4] | 4.33 | US 169 near Harcourt | Dayton | 1920 | 1940 | Spur route; replaced by an extended Iowa 175 | ||
| 4.18 | 6.73 | Ledyard | US 169 near Ledyard | 1940 | 1980 | Spur route; now County Road A30 | ||
| 4.643 | 7.472 | Iowa 9 in Lyon County | MN 91 at the Minnesota state line | 1980 | 2003 | Now County Road L14 (was K64 before 1980) | ||
| 1.33[4] | 2.14 | Iowa 101 near Urbana | Urbana | 1920 | 1939 | Spur route; became Iowa 363 | ||
| 274.231 | 441.332 | US 275 / N-92 in Council Bluffs | IL 92 at Muscatine | 1939 | current | Formerly Iowa 2 | ||
| 29.534 | 47.530 | US 63 near Tripoli | Iowa 150 in Fayette | 1920 | current | |||
| 13.12[6] | 21.11 | US 151 in Marion | US 30 in Mount Vernon | 1920 | 1958 | Replaced by relocated Iowa 150 | ||
| 11.168 | 17.973 | US 151 Business in Cedar Rapids | Palo | 1966 | 2003 | Spur route; now County Road W36 in Linn County and city streets in Cedar Rapids | ||
| 6 | 9.7 | US 169 near Bouton | Woodward | 1920 | 1932 | Spur route; replaced by an extended Iowa 89 | ||
| 3.70 | 5.95 | Carbon | Iowa 148 north of Corning | 1932 | 1983 | Spur route; section inside Carbon eliminated 1980; rest redesignated as unsigned Iowa 951 | ||
| 16.635 | 26.771 | Iowa 14 near Gladbrook | US 63 near Gladbrook | 1920 | current | |||
| 1.532 | 2.466 | Russell | US 34 near Russell | 1920 | 2003 | Spur route; much of route now County Road S56 with the last two blocks now Shaw Street | ||
| 11.10[8] | 17.86 | US 34 near Agency | Selma | 1920 | 1944 | Spur route; replaced by an extended Iowa 16, and Iowa 98 was reassigned to the old route of Iowa 16 | ||
| 1.814 | 2.919 | Leando | Iowa 16 near Douds | 1920 | 2017 | Spur route; originally began at Iowa 8 (later US 34) east of Agency, but was shortened to Iowa 16 near Douds in 1942 (this section became Iowa 16); now County Road V64 | ||
| 33 | 53 | US 30 near Camanche | US 61 in Davenport | 1920 | 1931 | Replaced by US 55 (later US 67) | ||
| 33.232 | 53.482 | US 34 in Burlington | US 61 in Wapello | 1931 | 2003 | Now County Road X99; was County Road 99 until 2005 | ||
| 44.42[6] | 71.49 | US 275 / Iowa 375 in Council Bluffs | US 71 in Lyman | 1920 | 1958 | Originally a spur route from Iowa 2/Iowa 24 (now US 6) to Griswold, this became part of Iowa 48 in 1923; east-west route designated 1921 when Iowa 24 was decommissioned through Lewis, replaced by relocated Iowa 92 | ||
| 6.12[16] | 9.85 | US 6 near Lewis | US 71 near Atlantic | 1958 | 1958 | Former section of Iowa 92; renumbered Iowa 414 due to confusion with old Iowa 100 | ||
| 16.140 | 25.975 | US 30 / US 218 in Cedar Rapids | US 151 / Iowa 13 near Marion | 1984 | current | Former portion of Iowa 150 | ||
| 15.56 | 25.04 | US 218 in Vinton | Iowa 150 north of Urbana | 1920 | 1984 | Replaced by a relocated Iowa 150 | ||
| 1.82 | 2.93 | Hawkeye | US 18 near Hawkeye | 1920 | 1980 | Now County Road W14 | ||
| Iowa 102 | 0.501 | 0.806 | New Sharon city limits | US 63 / Iowa 146 in New Sharon | 1980 | current | Unsigned highway; formerly extended to Pella (this is now County Road G5T) | |
| 15.649 | 25.185 | US 218 near Donnellson | US 61 / Iowa 2 in Fort Madison | 1920 | 2003 | Now County Road J40 | ||
| 20 | 32 | No. 8 near Council Bluffs | No. 4 in Macedonia | 1920 | 1926 | First highway to be decommissioned in Iowa; became a county road (now numbered G66) | ||
| 1.53 | 2.46 | Woodburn | US 34 near Woodburn | 1927 | 1980 | Spur route; now County Road R69; segment in Woodburn maintained as unsigned Iowa 942 until 2003 | ||
| 34.23[12] | 55.09 | US 69 in Lake Mills | US 218 in St. Ansgar | 1920 | 1992 | Section from US 69 to Winnebago–Worth county line last shows on 1994 map, so was signed until 1994; now County Road 105 | ||
| 8.98 | 14.45 | Iowa 107 in Clear Lake | US 65 in Mason City | 1920 | 1980 | Now local roads and County Road B35 | ||
| 27.579 | 44.384 | Iowa 3 near Alexander | CR B35 near Clear Lake | 1920 | 2011 | All but parts in Meservey and Thornton removed in 2003; now County Roads S25, B65 and S14 | ||
| 1.18 | 1.90 | Delta | Iowa 92 near Delta | 1923 | 1980 | Spur route; now County Road V33 and Iowa 21 | ||
| 1.268 | 2.041 | Oxford | US 6 near Oxford | 1923 | 2003 | Spur route; now County Road W38 | ||
| 0.7 | 1.1 | Larrabee | Iowa 73 in Larrabee | 1923 | 1934 | Spur route; decommissioned when Iowa 73 (proposed US 73, now US 59) was relocated to go through Larrabee; now a county road (455th Street) | ||
| 14.789 | 23.801 | US 20 at Schaller | Iowa 7 at Storm Lake | 1934 | current | |||
| 26.72[17] | 43.00 | Kanawha | Woden | 1923 | 1990 | Double spur route with US 18; originally a spur route; now County Road R35 | ||
| 3 | 4.8 | Iowa 13 | Edgewood | 1923 | 1930 | Spur route; replaced by an extended Iowa 10 (this section now Iowa 3) | ||
| 5.19 | 8.35 | Volga | Iowa 13 near Osborne | 1931 | 1980 | Spur route; now County Road C24 | ||
| 34.09[4] | 54.86 | Iowa 10 near Edgewood | US 151 in Monticello | 1924 | 1938 | Replaced by an extended Iowa 38 | ||
| 1.187 | 1.910 | Iowa 64 near Spragueville | Spragueville | 1938 | 2003 | Spur route; now County Road Z20 | ||
| 2.22[5] | 3.57 | Route 81 near Farmington | Iowa 2 near Farmington | 1923 | 1968 | Swapped with Iowa 81 | ||
| 9.20 | 14.81 | Iowa 92 near West Chester | Iowa 22 at Wellman | 1969 | 1981 | Formerly Iowa 81; now County Road W38 | ||
| 1.34[11] | 2.16 | US 69 | Story City | 1923 | 1969 | Spur route; now County Road E15 | ||
| 1.237 | 1.991 | US 34 near Stanton | Viking Lake State Park | 1980 | 2003 | Park access road; now County Roads M65 and H43 | ||
| 1.57[18] | 2.53 | US 20 near Manchester | Manchester Fish Hatchery | 1923 | 1976 | Fish hatchery access road; renumbered Iowa 938 because US 20 was rerouted | ||
| Iowa 116 | 2.776 | 4.468 | Iowa 3 in Waverly | US 218 near Waverly | 1998 | current | Section of US 218 Business in Waverly; signed as US 218 Business instead of Iowa 118 | |
| 63 | 101 | US 161 at Anamosa | US 52 / IL 64 at Savanna, Ill. | 1923 | 1936 | Swapped with Iowa 64 | ||
| 18.562 | 29.873 | Iowa 163 at Prairie City | US 65 / Iowa 330 near Mingo | 1939 | current | Formerly Iowa 64 | ||
| 4.06[17] | 6.53 | Steamboat Rock | Iowa 175 near Eldora | 1923 | 1989 | Spur route; now County Road S56 and a local road (Market Street) | ||
| 1.04 | 1.67 | Dorchester | Iowa 76 near Dorchester | 1923 | 1980 | Spur route; now County Road A16 | ||
| 0.80 | 1.29 | Stanton | US 34 near Stanton | 1924 | 1980 | Spur route; now County Road M63 | ||
| 0.51[19] | 0.82 | Dolliver Memorial State Park | Iowa 50 near Lehigh | 1924 | 1964 | Park access road; became a county road (now numbered D64) | ||
| 5.47[16] | 8.80 | Iowa 150 in Davenport | US 61 in Davenport | 1924 | 1960 | Now Pine Street, Cheyenne Avenue, Division Street, Locust Street, and Marquette Street | ||
| 3.04 | 4.89 | Iowa 3 near Clarksville | Clarksville | 1964 | 1965 | Former section of Iowa 188; became part of Iowa 188 again | ||
| 12.264 | 19.737 | I-35 / US 18 at Clear Lake | Mason City city limits | 1999 | current | |||
| 10.51 | 16.91 | I-35 in Des Moines | Iowa 90 in Des Moines | 1924 | 1959 | Partially replaced by Iowa 60; rest now Fleur Drive | ||
| 0.45 | 0.72 | US 34 near Rome | Rome | 1969 | 1980 | Spur route; inside Rome stayed in the highway system until 1981 | ||
| 2.567 | 4.131 | Iowa 4 in Calhoun County | Twin Lakes State Park | 1924 | 2003 | Park access road; now County Roads D26 and N57 | ||
| 3.26 | 5.25 | Salem | US 218 east of Salem | 1924 | 1981 | Spur route; section inside Salem deleted in 1980; now County Road J20 | ||
| 1.28 | 2.06 | US 6 near Mitchellville | Mitchellville | 1924 | 1980 | Spur route; now unsigned County Road S27 | ||
| 15.985 | 25.725 | I-29 near Mondamin | US 30 in Logan | 1924 | current | |||
| 6.982 | 11.236 | Iowa 13 near Elkader | US 52 near Garnavillo | 1924 | current | |||
| 0.45[11] | 0.72 | US 34 near Rome | Rome | 1924 | 1969 | Spur route; renumbered Iowa 123 when I-129 was designated | ||
| 12 | 19 | Iowa 9 near Cresco | Minnesota border near Harmony, Minn | 1925 | 1930 | Renumbered Iowa 139 so Iowa 130 could be reused as a spur of US 30 | ||
| 11 | 18 | Nebraska border | US 30 / US 75 in Missouri Valley | 1930 | 1931 | Formerly Iowa 27; replaced by relocated US 30 | ||
| 6.65[5] | 10.70 | Maquoketa Caves State Park | US 61 near Maquoketa | 1931 | 1966 | Park access road; became a county road (later numbered Y31); was Iowa 428 from 1980 to 2003 | ||
| 32.023 | 51.536 | Iowa 38 in Tipton | I-80 / US 61 at Davenport | 1969 | current | Former section of Iowa 150 | ||
| 2[10] | 3.2 | US 20 near Holstein | US 59 near Holstein | 1925 | 1937 | Section from US 20 to Holstein replaced by realigned US 59; rest given to county because US 59 was realigned | ||
| 4.520 | 7.274 | Iowa 21 in Belle Plaine | US 30 near Belle Plaine | 1937 | 2003 | Part of the Lincoln Highway; now County Road V40 | ||
| 5.74[19] | 9.24 | I-35 / I-80 in Des Moines | Iowa 90 (now US 6) in Des Moines | 1925 | 1963 | Now Douglas Avenue | ||
| 4.23[16] | 6.81 | US 34 / US 218 in Mount Pleasant | Oakland Mills Park (then a state park) | 1925 | 1961 | Park access road; became a county road (now numbered H61) | ||
| 0.970 | 1.561 | US 30 in Nevada | Nevada | 1964 | 2003 | Spur route; now 6th Street | ||
| 7 | 11 | US 65 near Hubbard | Iowa 58 | 1925 | 1930 | Replaced by relocated Iowa 58 | ||
| 8 | 13 | Nebraska state line | US 34 / US 275 in Glenwood | 1930 | 1935 | Replaced by relocated US 34 | ||
| 4.06 | 6.53 | US 65 near Hampton | Geneva | 1935 | 1980 | Spur route; now County Road C47 | ||
| 1.75[20] | 2.82 | Beed's Lake State Park | Iowa 3 near Hampton | 1980 | 1987 | Park access road; now County Road S42 | ||
| 0.75[21] | 1.21 | US 30 near Le Grand | Le Grand | 1926 | 1954 | Spur route; replaced by relocated US 30; Iowa 135 on route shown below | ||
| 1.96 | 3.15 | Montour | US 30 near Montour | 1954 | 1980 | Spur route; now County Road T47 | ||
| 87.611 | 140.996 | IL 136 at Clinton | US 20 / US 52 at Dyersville | 1926 | current | |||
| 21 | 34 | US 34 at Lucas | US 65 near Indianola | 1926 | 1934 | Formerly No. 65; replaced by realigned US 65 | ||
| 14.526 | 23.377 | Iowa 5 at Albia | US 63 / Iowa 163 at Eddyville | 1934 | current | Formerly Iowa 59 | ||
| 3.16[22] | 5.09 | Iowa 2 near Mystic | Mystic | 1926 | 1973 | Formerly No. 69; now County Road T14 | ||
| 21 | 34 | US 161 in Iowa City | Iowa 38 near Rochester | 1926 | 1929 | Formerly No. 74; replaced by an extended Iowa 1 | ||
| 11.431 | 18.396 | Iowa 9 near Cresco | MN 139 near Harmony, Minn | 1930 | current | Formerly Iowa 130; continued south to Protivin from 1935 to 1980 | ||
| 25.309 | 40.731 | US 20 at Moville | Iowa 3 at Remsen | 1926 | current | Formerly No. 30; continued south to Sloan from 1931 to 1961, and to Hornick from 1961 to 1964; section from Kingsley to Remsen deleted in 1965, but restored in 1980 | ||
| 155.362 | 250.031 | I-29 near Sloan | I-35 / I-80 at Grimes | 1926 | current | |||
| 10.50[5] | 16.90 | Route 202 at Coatsville, Mo | Iowa 2 near Moulton | 1926 | 1968 | Former Iowa 71; renumbered Iowa 202 | ||
| 20.901 | 33.637 | Iowa 2 in Plano | Iowa 5 near Moravia | 1980 | 2003 | Now County Roads S70 and J18 | ||
| 12.049 | 19.391 | Iowa 3 at Marcus | Iowa 10 at Granville | 1926 | current | |||
| 34.039 | 54.780 | Iowa 141 at Perry | Iowa 175 near Harcourt | 1926 | current | |||
| 5 | 8.0 | Iowa 5 near Cleghorn | Cleghorn | 1926 | 1931 | Formerly No. 32; became a county road (now numbered L40) | ||
| 7.408 | 11.922 | I-29 near Thurman | US 275 near Sidney | 1931 | 2003 | Originally a spur route west to Thurman; extended west in 1980; now County Road J24 | ||
| 42.735 | 68.775 | US 63 / Iowa 102 in New Sharon | US 30 in Le Grand | 1926 | current | |||
| 6.706 | 10.792 | Rockford | Iowa 14 in Floyd County | 1926 | 2003 | Spur route, former Iowa 53; now County Road B45 | ||
| 66.828 | 107.549 | Route 148 near Bedford | I-80 / US 6 near Anita | 1926 | current | |||
| 65.897 | 106.051 | US 34 in Ottumwa | I-80 near Williamsburg | 1926 | current | Section from I-80 to US 6 removed 1985 | ||
| 19 | 31 | US 32 at Homestead | US 30 near Cedar Rapids | 1926 | 1930 | Formerly No. 13; replaced by an extended Iowa 149 | ||
| 10 | 16 | Schleswig | Iowa 141 near Denison | 1930 | 1930 | Replaced by an extended Iowa 21 | ||
| 22.96 | 36.95 | US 30 / Iowa 17 in Jefferson | Iowa 64 in Panora | 1931 | 1941 | Replaced by relocated Iowa 17 to avoid conflict with new Iowa 150, which was proposed to become part of US 150 | ||
| 85.093 | 136.944 | US 218 at Vinton | US 52 / Iowa 24 at Calmar | 1941 | current | |||
| 13[10] | 21 | US 71 at Auburn | Iowa 17 near Lake City | 1926 | 1938 | Formerly No. 35; renumbered Iowa 188 when US 151 extended into Iowa | ||
| 1.31 | 2.11 | US 34 near Murray | Murray | 1926 | 1980 | Formerly No. 8; now County Road R16 | ||
| 1.402 | 2.256 | I-35 near Osceola | US 69 at Osceola | 1980 | 2014 | Now County Road R35 | ||
| 7.0 | 11.3 | Iowa 117 in Wyoming | Oxford Junction | 1926 | 1930 | Replaced by an extended Iowa 136 | ||
| 4.82[6] | 7.76 | US 218 near North Liberty | US 6 near Coralville | 1930 | 1957 | Replaced by rerouted US 218 and local roads | ||
| 1.02[5] | 1.64 | US 218 near North Liberty | North Liberty | 1957 | 1968 | Former portion of US 218; now Dubuque Street | ||
| 12.82 | 20.63 | Iowa 150 near Fayette | Iowa 3 in Maryville | 1926 | 1980 | Replaced by Iowa 187 | ||
| 7.0 | 11.3 | Commerce | Iowa 28 (now 9th Street) in Des Moines | 1927 | 1931 | Spur route; now Walnut Woods Drive, Browns Woods Drive, and McKinley Avenue; parts of the road were destroyed | ||
| 3.05 | 4.91 | Nodaway | US 34 near Nodaway | 1933 | 1980 | Spur route; now County Road N26, 8th Avenue and 3rd Street | ||
| 4.748 | 7.641 | Iowa 5 near Marysville | Bussey | 1928 | 2003 | Spur route, section inside Bussey removed 1980; now County Road G71 | ||
| 0.15 | 0.24 | Monticello | US 161 near Monticello | 1928 | 1931 | Spur route; now Cedar Street; was the shortest state highway at the time | ||
| 1.032 | 1.661 | US 63 near Lime Springs | Lime Springs | 1931 | 2003 | Spur route; now County Road A21 | ||
| 0.65[16] | 1.05 | Iowa 60 near Carlisle | Carlisle | 1929 | 1962 | Spur route; now School Street | ||
| 1.83 | 2.95 | Iowa 92 near Harper | Harper | 1929 | 1980 | Spur route; now County Road V67 | ||
| 0.82[8] | 1.32 | Wild Cat Den State Park | US 61 | 1930 | 1947 | Renumbered Iowa 389 so Iowa 160 could be reused as a spur of Iowa 60 (this section now Iowa 415) | ||
| 2.446 | 3.936 | Iowa 415 at Ankeny | I-35 at Ankeny | 1947 | current | extended east from US 69 to I-35 in 1980 | ||
| 1.15[8] | 1.85 | Iowa 25 in Guthrie County | Springbrook State Park | 1938 | 1944 | Renumbered Iowa 384 so Iowa 161 could be reused as a spur of US 61 | ||
| 0.47[23] | 0.76 | US 61 in Keokuk | Illinois state line | 1944 | 1951 | Replaced by US 136 | ||
| 1.224 | 1.970 | Iowa 141 at Dedham | Iowa 141 near Dedham | 1951 | 2003 | Former route of Iowa 141; now County Roads E60 and N33 | ||
| 2.660 | 4.281 | Pammel State Park | Iowa 92 in Madison County | 1930 | 1982 | Park access road; renumbered Iowa 322 to avoid confusion with nearby US 169 | ||
| Iowa 162 | 2.0 | 3.2 | US 18 in Charles City | US 218 in Charles City | 2000 | 2006 | Former section of US 218; became part of relocated US 18 | |
| 1 | 1.6 | Ambrose A. Call State Park | US 169 near Algona | 1930 | 1934 | Park access road; renumbered Iowa 274 when US 163 was designated | ||
| 166.270 | 267.586 | US 69 in Des Moines | US 34 at Burlington | 1937 | current | |||
| 3.79[17] | 6.10 | US 30 in Boone | Ledges State Park | 1930 | 1990 | Park access road; now County Road R27 | ||
| 4.67[21] | 7.52 | Lewis and Clark State Park | US 75 in Onawa | 1930 | 1955 | Park access road; replaced by an extended Iowa 175 | ||
| 0.410 | 0.660 | Abbott Drive at Omaha, Neb. | Abbott Drive at Omaha, Neb. | 1956 | current | Only state highway west of the Missouri River | ||
| 0.57 | 0.92 | Hastings | US 34 near Hastings | 1930 | 1980 | Spur route; now County Road M16 | ||
| 3.21 | 5.17 | Doon | US 75 near Doon | 1930 | 1980 | Spur route; now Main Street, 3rd Avenue and County Road A44 | ||
| 2.70 | 4.35 | Iowa 83 near Minden | Shelby | 1930 | 1980 | Spur route; now County Road M16 | ||
| 3 | 4.8 | Elk Horn | Iowa 7 at Kimballton | 1930 | 1930 | Spur route; renumbered Iowa 173 when US 169 was created in Iowa | ||
| 1.68[22] | 2.70 | Everly | US 18 near Everly | 1930 | 1974 | Spur route, former portion of US 18; now County Road M27 | ||
| 1 | 1.6 | Wall Lake State Park (now Big Wall Lake Wildlife Area) | US 75 in Onawa | 1930 | 1935 | Park access road; now an unnumbered county road | ||
| 1.05 | 1.69 | Elberon | Iowa 21 near Elberon | 1935 | 1980 | Spur route; now Main Street and County Road E44 | ||
| 4.23 | 6.81 | Elgin | US 18 in Clermont | 1930 | 1980 | Spur route; now County Road W51 and Main, Clermont and Center Streets | ||
| 14.680 | 23.625 | Iowa 83 near Atlantic | Iowa 44 at Kimballton | 1930 | current | Originally a spur route south to Elk Horn; extended in 1980 | ||
| 3.61[18] | 5.81 | Farragut | Iowa 2 near Farragut | 1930 | 1976 | Spur route; now County Road M16 | ||
| 221.367 | 356.256 | N-51 at Decatur, Neb | US 63 near Hudson | 1930 | current | Originally a spur route | ||
| 1.21[13] | 1.95 | Iowa 92 near Cumberland | Cumberland | 1930 | 1972 | Spur route; now County Road N28 and Jackson, 1st, and Main Streets | ||
| 1 | 1.6 | Carson | US 59 near Carson | 1930 | 1937 | Spur route; decommissioned when Iowa 100 (now Iowa 92) extended west through Carson | ||
| 3.20 | 5.15 | Iowa 9 near Osage | Mitchell | 1937 | 1980 | Spur route; now County Road T28 | ||
| 0.98 | 1.58 | Iowa 9 near Little Rock | Little Rock | 1930 | 1980 | Spur route; now Main Street and Maple Avenue | ||
| 0.82 | 1.32 | US 69 near Klemme | Klemme | 1930 | 1980 | Spur route; now 168th Street and Main Street | ||
| 2.46 | 3.96 | Hayesville | Iowa 149 near Hayesville | 1930 | 1980 | Spur route; now County Road G49 | ||
| 3 | 4.8 | Riverside | US 161 near Riverside | 1930 | 1931 | Spur route; replaced by an extended Iowa 22 | ||
| 9.596 | 15.443 | Iowa 5 / Iowa 92 near Pleasantville | Melcher-Dallas | 1931 | 2003 | Spur route; now County Road S45 | ||
| 11.44[5] | 18.41 | Iowa 9 in Lansing | MN 26 at New Albin | 1930 | 1968 | Swapped with Iowa 26 | ||
| 9.051 | 14.566 | US 18 in Inwood | Iowa 9 near Larchwood | 1969 | current | Formerly Iowa 26 | ||
| 29.952 | 48.203 | Iowa 127 near Mondamin | Iowa 141 in Ute | 1930 | current | Continued south to US 6 until 1981, and to Council Bluffs city limits until 2003 | ||
| 26 | 42 | Blockton | US 34 near Creston | 1930 | 1932 | Spur route; replaced by an extended Iowa 25 | ||
| 15.026 | 24.182 | US 275 near Randolph | US 59 near Randolph | 1934 | 2003 | Originally a spur route from US 275 to Randolph; now County Road J18 | ||
| 1.51[24] | 2.43 | Iowa 14 near Conrad | Conrad | 1934 | 1978 | Spur route; now County Road D67 | ||
| 3.27 | 5.26 | US 34 near Prescott | Prescott | 1930 | 1980 | Spur route; now County Road N61 and 6th Avenue | ||
| 3.375[25] | 5.432 | Green Valley State Park | Iowa 25 in Creston | 1980 | 2001 | Park access road; now unnumbered county roads (Green Valley Road and 130th Street) and Lincoln Street | ||
| 9 | 14 | Iowa 10 in Alton | Hospers | 1930 | 1931 | Spur route; replaced by Iowa 33 | ||
| 28.385 | 45.681 | US 20 near Masonville | Iowa 150 near Fayette | 1931 | current | Originally was a park access road to Backbone State Park; moved to current route in 1980 | ||
| 26[10] | 42 | US 52 / Iowa 10 at Luxemburg | US 161 at Cascade | 1930 | 1938 | Replaced by an extended Iowa 136 | ||
| 13 | 21 | US 71 at Auburn | Iowa 17 near Lake City | 1938 | 1940 | Formerly No. 35 and Iowa 151; replaced by an extended Iowa 175 | ||
| 24.231 | 38.996 | Iowa 3 near Clarksville | US 63 near Tripoli | 1945 | current | |||
| 1.00 | 1.61 | Bridgewater | Iowa 92 north or Bridgwater | 1930 | 1980 | Spur route; now County Road N51 | ||
| 10 | 16 | Ashton | Iowa 9 in Sibley | 1930 | 1931 | Spur route; replaced by Iowa 33 | ||
| 7.46 | 12.01 | Fairbank | Iowa 150 near Oelwein | 1931 | 1980 | Replaced by Iowa 281 | ||
| 22.790 | 36.677 | I-680 near Neola | Iowa 37 at Earling | 1930 | current | continued south to US 6 until 1981, and to Council Bluffs city limits until 2003 | ||
| 10 | 16 | US 75 in Sloan | Iowa 141 near Hornick | 1930 | 1931 | Became part of an extended Iowa 140 | ||
| 5.090 | 8.192 | I-29 / I-80 at Council Bluffs | I-29 at Council Bluffs | 1931 | 2017 | Renumbered from Iowa 241; was decommissioned in 1975, but restored in 1980; truncated in 2016; now city streets | ||
| 10.852 | 17.465 | US 18 in Fayette County | Iowa 24 in Jackson Junction | 1930 | 2003 | Now County Road V68 | ||
| 0.86[6] | 1.38 | Iowa 2 in Clarinda | Clarinda Treatment Center | 1930 | 1958 | Hospital access road; now 16th Street | ||
| 3[10] | 4.8 | US 69 in Jewell | Ellsworth | 1930 | 1935 | Spur route; became part of an extended Iowa 175 | ||
| 2.896 | 4.661 | Iowa 4 near Plover | Plover | 1935 | 2003 | Spur route; now County Road C15 | ||
| 1 | 1.6 | US 20 near Williams | Williams | 1930 | 1932 | Was proposed to replace part of US 20, which was to be shifted south, but the plan to relocate US 20 was abandoned in 1932; portion now County Road D25 | ||
| 10.136 | 16.312 | US 71 / Iowa 175 near Lake View | US 20 near Sac City | 1935 | 2015 | Replaced by a rerouted US 71 | ||
| 7[10] | 11 | Stratford | Iowa 60 near Stanhope | 1930 | 1937 | Spur route; became part of an extended Iowa 175 | ||
| 2.567 | 4.131 | Iowa 3 near Albert City | Albert City | 1937 | 2003 | Spur route; now Main Street and County Road N14 | ||
| 2.231 | 3.590 | Garrison | US 218 near Garrison | 1930 | 2003 | Spur route, section in Garrison removed 1980; now County Road V66 | ||
| 2.666 | 4.291 | Van Horne | US 218 near Van Horne | 1930 | 2003 | Spur route, section in Van Horne removed 1980; now County Road E44 | ||
| 2.163 | 3.481 | US 30 near Keystone | Keystone | 1930 | 2003 | Spur route, section in Keystone removed 1980; now County Road V42 | ||
| 4.755 | 7.652 | Norway | US 30 / US 218 near Atkins | 1930 | 2003 | Spur route; now County Road W24 | ||
| 8.13[5] | 13.08 | US 218 | Shellsburg | 1930 | 1967 | Spur route; became a county road (now numbered E36) | ||
| 10.461 | 16.835 | Route 202 at Coatsville, Mo | Iowa 2 near Moulton | 1969 | current | Formerly Iowa 142 | ||
| 8.78 | 14.13 | Terril | Iowa 9 | 1930 | 1980 | Spur route; original east-west spur now County Road A34, north-south spur now County Road N14, Main and State streets | ||
| 5.407 | 8.702 | Iowa 2 near Garden Grove | Garden Grove | 1930 | 2003 | Spur route; now County Roads R20 and J69 | ||
| 2.927 | 4.711 | US 65 near Milo | Milo | 1930 | 2003 | Spur route; now County Road G58 | ||
| 6.221 | 10.012 | US 65 near Liberty Center | Liberty Center | 1930 | 2003 | Spur route; now County Road G76 | ||
| 3.058 | 4.921 | I-35 near New Virginia | New Virginia | 1930 | 2003 | Spur route; now County Road G76 | ||
| 14 | 23 | US 20 | Backbone State Park | 1930 | 1931 | Park access road; renumbered Iowa 187 | ||
| 11.83[22] | 19.04 | Iowa 2 | Blanchard | 1931 | 1974 | Spur route; now County Road M48 | ||
| 0.66[18] | 1.06 | Iowa 149 near Conroy | Conroy | 1931 | 1976 | Spur route; now County Road F34 | ||
| 34.781 | 55.975 | Iowa 141 near Woodward | US 65 near Collins | 1931 | current | Originally a double spur route from Slater to Maxwell; extended in 1980 | ||
| 1.63 | 2.62 | Cambridge | Iowa 210 near Cambridge | 1931 | 1980 | Spur route; now County Road R70 | ||
| 20 | 32 | Iowa 8 in Dysart | US 30 in Belle Plaine | 1931 | 1933 | Replaced by an extended Iowa 73, which was renumbered Iowa 212 9 months later; this portion became part of Iowa 21 a month later | ||
| 12.157 | 19.565 | Iowa 21 near Belle Plaine | US 6 at Marengo | 1934 | current | continued northwest to US 30 from 1937 to 1980 | ||
| 3.72 | 5.99 | Blakesburg | US 34 north of Blakesburg | 1931 | 1980 | Spur route; now County Road T61 | ||
| 5.736 | 9.231 | Iowa 175 near Ivester | Wellsburg | 1931 | 2003 | Spur route; now County Road T19 | ||
| 8.738 | 14.062 | Union | Iowa 175 in Eldora | 1931 | 2003 | Spur route; now County Road S62 | ||
| 1.70[15] | 2.74 | Iowa 5 | Exline | 1931 | 1981 | Spur route; now County Road T16 | ||
| 4.96[17] | 7.98 | Breda | US 71 | 1931 | 1989 | Spur route; now County Road E16 | ||
| 1.53 | 2.46 | Iowa 9 near Lake Park | Lake Park | 1931 | 1980 | Spur route; now County Road M27 | ||
| 7.233 | 11.640 | US 6 at South Amana | US 151 at Amana | 1931 | current | Continued east to East Amana and south to Upper South Amana until 1980 | ||
| 11[10] | 18 | US 71 near Albert City | Albert City | 1931 | 1937 | Spur route; became a county road (now numbered C29) | ||
| 42.61[8] | 68.57 | Iowa 5 near Cherokee | Iowa 17 / Iowa 10 at Pocahontas | 1937 | 1945 | Extended in both directions and renumbered Iowa 3 | ||
| 3.909 | 6.291 | I-35 near Story City | Roland | 1947 | 2003 | Spur route, section from I-35 to US 69 removed 1980; now County Road E18 | ||
| 15.12 | 24.33 | Iowa 15 near Ottosen | Livermore | 1931 | 1980 | Spur route; now County Road C20 | ||
| 12.22[9] | 19.67 | Iowa 330 near Baxter | Iowa 14 near Baxter | 1931 | 1997 | Originally a spur route, extended west from Baxter in 1980; now County Road F17 | ||
| 10.587 | 17.038 | US 6 near Kellogg | Iowa 14 near Laurel | 1931 | current | Originally a spur route; extended north from Kellogg in 1980 | ||
| 7.688 | 12.373 | Sully | Iowa 146 in Searsboro | 1931 | 2003 | Spur route; now County Road F62 | ||
| 10.78 | 17.35 | US 18 | Titonka | 1931 | 1980 | Spur route; now County Road P64 | ||
| 5.39[26] | 8.67 | US 218 near Stacyville | Stacyville | 1931 | 1991 | Spur route; now County Road T40 | ||
| 0.85[19] | 1.37 | US 6 (this section became County Road F58 in 2003) near Walcott | Walcott | 1931 | 1964 | Spur route; now Main Street | ||
| 5.233 | 8.422 | Garwin | US 63 in Tama County | 1931 | 2003 | Spur route; now County Road E29 | ||
| 1[10] | 1.6 | Sergeant Bluff | US 75 near Sergeant Bluff | 1931 | 1934 | Spur route; decommissioned because US 75 was rerouted through Sergeant Bluff, and Iowa 230 was reassigned to the old route of US 75; part later restored as Iowa 378 in 1942 | ||
| 8.60[19] | 13.84 | US 75 near Sergeant Bluff | US 75 in Sioux City | 1934 | 1965 | Spur route; now Transit Avenue, Morningside Avenue, Lakeport Road and a county road (now numbered K29) | ||
| 1.83[15] | 2.95 | Iowa 10 near Ireton | Ireton | 1931 | 1981 | Spur route; now County Road K30 and 4th Street | ||
| Iowa 231 | 4.068 | 6.547 | US 34 west of New London | US 34 east of New London | 2000 | 2003 | Former section of US 34, unsigned; now Main Street | |
| 1.99 | 3.20 | Earlham | I-80 near Earlham | 1931 | 1980 | Spur route; now County Road P57 | ||
| 5.30[17] | 8.53 | Albion | Iowa 14 near Rhodes | 1931 | 1989 | Spur route; became part of relocated Iowa 330 | ||
| 6.72[17] | 10.81 | US 30 in State Center | Iowa 330 near Rhodes | 1931 | 1994 | Originally a spur route; only the section north of CR E63 remained after 1989; now an unnumbered county road | ||
| 3 | 4.8 | Iowa 234 near Rhodes | Rhodes | 1931 | 1935 | Spur route; became an unnumbered county road (now 285th Street) | ||
| 1.24[5] | 2.00 | Rhodes | Iowa 234 near Rhodes | 1935 | 1966 | Spur route; renumbered Iowa 245 when I-235 was designated | ||
| 1.18[20] | 1.90 | Templeton | US 71 / Iowa 141 near Templeton | 1931 | 1987 | Spur route; now local roads (Main and 2nd Streets) and County Road N18 | ||
| 1.41 | 2.27 | Iowa 9 near Ocheyedan | Ocheyedan | 1931 | 1981 | Spur route; section in Ocheyedan removed in 1980; now County Road L58 | ||
| 1.063 | 1.711 | Iowa 9 near Harris | Harris | 1931 | 2003 | Spur route; was decommissioned in 1981, but was restored in 1987; now County Road M20 | ||
| 0.510 | 0.821 | Waubonsie State Park | Iowa 2 in Fremont County | 1931 | 2003 | Park access road; now County Road L48 | ||
| 6.389 | 10.282 | Royal | US 71 in Clay County | 1931 | 2003 | Spur route; now Main Street, County Roads M36 and B40 | ||
| 5 | 8.0 | US 34 / US 275 at Council Bluffs | US 34 / US 275 | 1931 | 1931 | Renumbered Iowa 192 | ||
| 0.99 | 1.59 | Readlyn | Iowa 3 near Readlyn | 1931 | 1980 | Spur route; now local roads | ||
| 5.855 | 9.423 | US 34 in Mills County | Silver City | 1931 | 2003 | Spur route; now County Road L55 | ||
| 7.97 | 12.83 | Iowa 140 near Kingsley | Pierson | 1931 | 1980 | Spur route; now County Road D12 | ||
| 0.559 | 0.900 | Black Hawk Lake State Park | US 71 / Iowa 175 near Wall Lake | 1980 | 2003 | Park access road; now an unnumbered county road | ||
| 1.96 | 3.15 | Henderson | US 59 | 1931 | 1980 | Spur route; now County Roads H12 and M21 and Maple Street | ||
| 0.771 | 1.241 | I-80 near Neola | Iowa 191 in Neola | 1980 | 2003 | Now County Road L55 | ||
| 1.54[16] | 2.48 | Iowa 9 near Estherville | Fort Defiance State Park | 1931 | 1961 | Park access road; became a county road (now numbered N26) | ||
| 1.24[17] | 2.00 | Rhodes | Iowa 234 near Rhodes | 1966 | 1990 | Spur route; portion outside of Rhodes removed in 1989; now County Road E63 | ||
| 3.26 | 5.25 | US 61 in Zwingle | La Motte | 1931 | 1981 | Spur route; section outside La Motte deleted in 1980; now County Road D55 and city streets | ||
| 0.68[19] | 1.09 | Chelsea | Iowa 212 near Chelsea | 1931 | 1963 | Spur route; became a county road (now numbered V18) | ||
| 0.54 | 0.87 | Independence State Hospital | US 20 in Independence | 1931 | 1980 | Hospital access road; now 20th Avenue SW | ||
| 0.665 | 1.070 | Iowa 78 near Winfield | Winfield | 1931 | 2003 | Spur route; now County Road V66 | ||
| 0.59 | 0.95 | Lakota | US 169 / Iowa 9 near Lakota | 1932 | 1980 | Spur route; now a local road | ||
| 1.71 | 2.75 | St. Charles | I-35 near St. Charles | 1932 | 1980 | Spur route; now County Road G50 | ||
| 0.584 | 0.940 | US 61 / Iowa 92 near Grandview | Grandview | 1932 | 2003 | Spur route | ||
| 0.932 | 1.500 | Iowa 14 near Williamson | Williamson | 1932 | 2003 | Spur route | ||
| 0.45[5] | 0.72 | Iowa 92 at Massena | Massena | 1932 | 1968 | Spur route; renumbered Iowa 322 | ||
| 7.91 | 12.73 | Iowa 9 near Buffalo Center | MN 254 near Rake | 1969 | 1980 | Spur route; formerly Iowa 322 | ||
| Iowa 254 | 2.7 | 4.3 | dead end northwest of Nashua | dead end southeast of Nashua | 2003 | 2004 | Former section of US 218 | |
| 2.26 | 3.64 | Orchard | US 218 near Orchard | 1932 | 1980 | Spur route | ||
| 0.80 | 1.29 | Iowa 17 near Corwith | Corwith | 1932 | 1980 | Spur route | ||
| 0.58[16] | 0.93 | US 18 near Dickens | Dickens | 1933 | 1960 | Spur route | ||
| 1.989 | 3.201 | I-35 near Van Wert | US 69 near Van Wert | 1933 | 2003 | Originally a spur route | ||
| 1.001 | 1.611 | US 169 near Tingley | Tingley | 1933 | 2003 | Spur route; section in Tingley removed 1980 | ||
| 2.12[24] | 3.41 | Shannon City | US 169 near Shannon City | 1933 | 1977 | Spur route | ||
| 33.02[16] | 53.14 | Iowa 1 in Iowa City | US 151 | 1930 | 1962 | Numbered as a branch of US 161; replaced by relocated Iowa 1 | ||
| 1.99 | 3.20 | US 69 near Galt | Galt | 1933 | 1980 | Spur route | ||
| 2.14 | 3.44 | Coulter | Latimer | 1933 | 1980 | Double spur route with Iowa 3 | ||
| Iowa 263 | 12.511 | 20.135 | Iowa 14 in Grundy County | US 20 near Cedar Falls | 2000 | 2003 | Former section of US 20 | |
| 2.39 | 3.85 | Linn Grove | Iowa 10 near Linn Grove | 1933 | 1980 | Spur route | ||
| 2.08[16] | 3.35 | Kent | US 34 near Kent | 1934 | 1961 | Spur route | ||
| 1.709 | 2.750 | US 69 near Weldon | Weldon | 1934 | 2003 | Spur route; section in Weldon removed 1980 | ||
| 1.19 | 1.92 | Iowa 93 near Randalia | Randalia | 1934 | 1980 | Spur route | ||
| 6.29[13] | 10.12 | US 59 near Irwin | Irwin | 1934 | 1971 | Spur route; became part of an extended Iowa 37 | ||
| 3.01 | 4.84 | Iowa 16 near Stockport | Stockport | 1934 | 1980 | Spur route | ||
| 1.80 | 2.90 | Iowa 16 near Hillsboro | Hillsboro | 1934 | 1980 | Spur route | ||
| 7[10] | 11 | Marne | US 71 in Atlantic | 1934 | 1935 | Spur route; replaced by an extended Iowa 83 | ||
| 0.84 | 1.35 | Iowa 4 near Yale | Yale | 1935 | 1980 | Spur route | ||
| 6.45[26] | 10.38 | Elma | US 63 near Elma | 1934 | 1992 | Spur route; formerly Iowa 52 | ||
| 10.025 | 16.134 | Lake Wapello State Park | US 63 near Drakesville | 1935 | 2003 | Park access road | ||
| 1.99[12] | 3.20 | Ambrose A. Call State Park | US 169 near Algona | 1934 | 1986 | Park access road; formerly Iowa 163 | ||
| 4.711 | 7.582 | Spirit Lake city limits | Minnesota state line | 1934 | 2003 | Park access road | ||
| 6.24 | 10.04 | Numa | Iowa 5 near Centerville | 1935 | 1980 | Spur route | ||
| 2.05 | 3.30 | Rathbun | Iowa 5 near Rathbun | 1935 | 1980 | Spur route | ||
| 1.983 | 3.191 | US 30 / US 218 near Atkins | Atkins | 1935 | 2003 | Spur route; section in Atkins removed 1980 | ||
| 2.62[19] | 4.22 | US 30 / US 218 near Newhall | Newhall | 1935 | 1965 | Spur route; renumbered Iowa 287 when I-280 was designated | ||
| 28.166 | 45.329 | Waterloo city limits | Iowa 150 at Oelwein | 1935 | current | Originally a spur route east to Dunkerton; extended in 1980 | ||
| 5.283 | 8.502 | Quasqueton | Iowa 939 near Winthrop | 1935 | 2003 | Spur route | ||
| 5.861 | 9.432 | Brandon | Iowa 150 near Brandon | 1935 | 2003 | Spur route | ||
| 5.58 | 8.98 | Aurora | Iowa 187 at Lamont | 1935 | 1980 | Spur route | ||
| 0.796 | 1.281 | US 30 in Arcadia | Arcadia | 1935 | 2003 | Spur route | ||
| 9.932 | 15.984 | US 30 in Glidden | Lanesboro | 1935 | 2003 | Spur route | ||
| 7.52[4] | 12.10 | Farnhamville | Iowa 47 in Farnhamville | 1935 | 1940 | Spur route; replaced by an extended Iowa 175 | ||
| 6.19[19] | 9.96 | Bradgate | Iowa 3 in Gilmore City | 1942 | 1965 | Spur route | ||
| 1.833 | 2.950 | US 30 / US 218 near Newhall | Newhall | 1965 | 2003 | Spur route; section in Newhall removed 1980 | ||
| 4.58 | 7.37 | US 65 near Manly | Plymouth | 1935 | 1980 | Spur route | ||
| 6.14 | 9.88 | Alta Vista | US 63 near Lourdes | 1935 | 1980 | Spur route | ||
| Iowa 289 | 2.252 | 3.624 | US 61 near Fort Madison | US 61 near Fort Madison | 2000 | 2003 | Former section of US 61 southwest of Fort Madison; had two sections | |
| 1.99 | 3.20 | Farmersburg | Iowa 13 near Farmersburg | 1935 | 1980 | Spur route | ||
| 1.01 | 1.63 | Low Moor | US 30 near Low Moor | 1935 | 1979 | Spur route | ||
| 3.17 | 5.10 | Linden | Iowa 44 | 1935 | 1980 | Spur route | ||
| 1.42 | 2.29 | Iowa 90 near Van Meter | Van Meter | 1935 | 1980 | Spur route | ||
| 6.147 | 9.893 | Iowa 2 in Decatur County | Grand River | 1935 | 2003 | Spur route | ||
| 5.09 | 8.19 | Westgate | Iowa 150 near Maynard | 1935 | 1980 | Spur route | ||
| 4.44 | 7.15 | CR C24 near Wadena | Iowa 56 near Wadena | 1935 | 1980 | Spur route | ||
| Iowa 296 | 0.275[25] | 0.443 | — | — | 2000 | 2011 | Former section of Iowa 28 | |
| 4.25[4] | 6.84 | Alexander | Iowa 10 | 1935 | 1939 | Spur route; replaced by an extended Iowa 107 | ||
| 3.543 | 5.702 | Gilbertville | Raymond | 1940 | 2003 | Double spur with I-380 | ||
| 4.22[5] | 6.79 | Iowa 60 near Kamrar | Kamrar | 1935 | 1966 | Spur route; until 1958 went from US 69 to Kamrar | ||
| 5.556 | 8.942 | New Providence | Iowa 175 near Eldora | 1935 | 2003 | Spur route | ||
| 1.411 | 2.271 | Modale | I-29 near Modale | 1935 | 2003 | Spur route | ||
| 2.045 | 3.291 | I-29 near Little Sioux | Little Sioux | 1935 | 2003 | Spur route | ||
| 3.00 | 4.83 | Thor | Iowa 3 near Thor | 1935 | 1980 | Spur route | ||
| 3.51[15] | 5.65 | US 34 near Fairfield | Libertyville | 1935 | 1981 | Spur route | ||
| 1.59 | 2.56 | Iowa 78 near Ollie | Ollie | 1935 | 1980 | Spur route | ||
| 2.554 | 4.110 | Letts | US 61 / Iowa 92 near Letts | 1935 | 2003 | Spur route | ||
| 0.783 | 1.260 | US 65 near Derby | Derby | 1935 | 2003 | Spur route | ||
| 5.31[18] | 8.55 | US 169 near East Peru | East Peru | 1935 | 1975 | Spur route; decommissioned when US 169 was rerouted south of Winterset | ||
| 7.32[5] | 11.78 | US 63 near New Sharon | Barnes City | 1935 | 1966 | Spur route | ||
| 2.32 | 3.73 | Beacon | Iowa 137 in Oskaloosa | 1935 | 1980 | Spur route | ||
| 1.68[5] | 2.70 | Iowa 92 near Harvey | Harvey | 1935 | 1966 | Spur route | ||
| 4.73[17] | 7.61 | Liscomb | Iowa 14 near Liscomb | 1935 | 1989 | Spur route; section in Liscomb removed 1980 | ||
| 6.19 | 9.96 | Iowa 9 near Riceville | McIntire | 1935 | 1980 | Spur route | ||
| Iowa 312 | 0.883 | 1.421 | — | — | 2002 | 2003 | Former section of US 65; had two sections | |
| 1.591[25] | 2.560 | US 59 near Melvin | Melvin | 1935 | 2002 | Spur route; section in Melvin removed 1980 | ||
| 6.277 | 10.102 | Ayrshire | US 18 near Ruthven | 1935 | 2003 | Spur route | ||
| 4.158 | 6.692 | Iowa 4 near Palmer | Palmer | 1935 | 2003 | Spur route | ||
| 5.183 | 8.341 | Iowa 5 near Swan | Runnells city limits | 1935 | current | Spur route; continued south to Iowa 163 from 1981 to 2003 | ||
| 0.71 | 1.14 | US 65 near Zearing | Zearing | 1935 | 1980 | Spur route; continued west to McCallsburg until 1954 | ||
| 5.51 | 8.87 | Clutier | Iowa 21 near Clutier | 1935 | 1980 | Spur route | ||
| 0.50 | 0.80 | Gravity | Iowa 148 at Gravity | 1935 | 1980 | Spur route; continued east to Conway until 1961 | ||
| 4.25[19] | 6.84 | US 169 near Badger | Badger | 1935 | 1963 | Spur route | ||
| 6.03[19] | 9.70 | Clare | Iowa 5 near Clare | 1935 | 1963 | Spur route | ||
| 7.91[11] | 12.73 | Iowa 9 near Buffalo Center | MN 254 near Rake | 1935 | 1968 | Spur route; renumbered Iowa 254 | ||
| 0.45[13] | 0.72 | Iowa 92 at Massena | Massena | 1969 | 1972 | Spur route; formerly Iowa 254 | ||
| 2.660 | 4.281 | Pammel State Park | Iowa 92 in Madison County | 1982 | 2003 | Park access road; formerly Iowa 162 | ||
| 3.74 | 6.02 | Iowa 17 near Woolstock | Woolstock | 1935 | 1980 | Spur route | ||
| 0.79[21] | 1.27 | Lawton | US 20 near Lawton | 1935 | 1954 | Spur route; decommissioned when US 20 was rerouted closer to Lawton | ||
| 0.510 | 0.821 | Iowa 175 near Onawa | Lewis and Clark State Park | 1956 | 2003 | Park access road | ||
| 3.617 | 5.821 | Spillville | US 52 near Calmar | 1935 | 2003 | Spur route; section in Spillville removed 1980 | ||
| 2.18[15] | 3.51 | Bristow | Iowa 3 near Bristow | 1935 | 1981 | Spur route | ||
| 2.070 | 3.331 | Iowa 276 in Spirit Lake | near Orleans | 1935 | 2003 | Spur route | ||
| 2.29 | 3.69 | US 20 near Galva | Galva | 1935 | 1980 | Spur route | ||
| 4.85 | 7.81 | US 169 at Boxholm | Pilot Mound | 1935 | 1980 | Spur route | ||
| 2.31[8] | 3.72 | Ionia | US 18 near Ionia | 1935 | 1948 | Spur route; renumbered Iowa 393 so Iowa 330 could be reused as a spur of US 30 | ||
| 47.748 | 76.843 | I-80 / US 6 / US 65 at Altoona | Iowa 14 near Albion | 1948 | current | Originally went from US 30 to Marshalltown; extended west in 1969 and was relocated to bypass Marshalltown in 1989 | ||
| 1.83[5] | 2.95 | Eldridge | US 61 near Eldridge | 1935 | 1967 | Spur route | ||
| Iowa 331 | 3.801 | 6.117 | Dead end near I-35 in Des Moines | Iowa 28 in Des Moines | 2002 | 2005 | Former section of Iowa 5 | |
| 1.00 | 1.61 | Pilot Knob State Park | Iowa 9 near Forest City | 1935 | 1980 | Park access road | ||
| 1.558 | 2.507 | I-29 at Hamburg | US 275 in Hamburg | 1935 | current | Originally a spur route; section from county line to US 71 removed 1980; reassigned to current route that year, but section from US 275 to US 59 removed 2003 | ||
| 1.87 | 3.01 | US 63 near Frederika | Frederika | 1935 | 1980 | Spur route | ||
| Iowa 334 | 6.600[27] | 10.622 | — | — | 2006 | 2007 | Former section of US 34 | |
| 0.64 | 1.03 | Iowa 141 near Dawson | Dawson | 1935 | 1980 | Spur route | ||
| Iowa 335 | 1.536[25] | 2.472 | Iowa 163 in Otley | Iowa 163 in Otley | 1999 | 2001 | Former section of Iowa 163 | |
| 2.48 | 3.99 | Iowa 150 near Rowley | Rowley | 1936 | 1980 | Spur route | ||
| 3.36 | 5.41 | Iowa 9 near Grafton | Grafton | 1936 | 1980 | Spur route | ||
| Iowa 337 | 2.764[25] | 4.448 | US 218 in Charles City | US 18 in Charles City | 2000 | 2001 | Former section of US 218 | |
| Iowa 337 | 1.085[28] | 1.746 | US 151 in Langworthy | US 151 in Langworthy | 2003 | 2004 | Former section of US 151 | |
| 1.02[13] | 1.64 | Bondurant | US 65 | 1936 | 1972 | Spur route | ||
| 6.15[29] | 9.90 | George | Iowa 9 near George | 1936 | 2000 | Spur route | ||
| 2.231 | 3.590 | Pikes Peak State Park | Iowa 76 in McGregor | 1936 | 2003 | Park access road | ||
| Iowa 340 | 1.160[27] | 1.867 | Dead end in Batavia | US 34 in Batavia | 2005 | 2007 | Former section of US 34 | |
| 2.10[20] | 3.38 | Lost Island Park | US 18 near Ruthven | 1936 | 1988 | Park access road | ||
| Iowa 341 | 0.062 | 0.100 | Ruthven | US 18 near Ruthven | 1993 | 2003 | Spur route; restoration of part of the previous Iowa 341 | |
| 0.95 | 1.53 | Iowa 141 near Jamaica | Jamaica | 1936 | 1980 | Spur route | ||
| Iowa 342 | 2.2 | 3.5 | Dead end north of Eddyville | Iowa 137 in Eddyville | 2004 | 2005 | Former section of US 63 | |
| 1.01 | 1.63 | Iowa 333 near Northboro | Northboro | 1937 | 1980 | Spur route | ||
| 7.06[8] | 11.36 | Iowa 2 in Bedford | Iowa 319 near Conway | 1937 | 1943 | Park access road; became part of an extended Iowa 49 | ||
| 1.075[25] | 1.730 | State fish hatchery | US 169 near Mount Ayr | 1943 | 2001 | Fish hatchery access road | ||
| 0.42[16] | 0.68 | Iowa 17 near Graettinger | Graettinger | 1937 | 1960 | Spur route | ||
| 12.470 | 20.069 | US 218 / Iowa 27 at Nashua | US 18 / US 63 near New Hampton | 1937 | current | |||
| 1.08[12] | 1.74 | Locust Street at Omaha, Neb. | Locust Street at Omaha, Neb. | 1937 | 1986 | |||
| 0.88[5] | 1.42 | Iowa 347 | Carter Lake | 1937 | 1967 | |||
| 1.032 | 1.661 | Lake Ahquabi State Park | US 65 / US 69 near Indianola | 1938 | 2003 | Park access road | ||
| 2.55[6] | 4.10 | US 6 near Davenport | Iowa 122 in Davenport | 1938 | 1958 | Now Hickory Grove Road | ||
| 0.86 | 1.38 | Rembrandt | US 71 near Rembrandt | 1938 | 1981 | Spur route; section in Rembrandt removed 1980 | ||
| 0.75 | 1.21 | Truesdale | US 71 near Truesdale | 1938 | 1981 | Spur route; section in Truesdale removed 1980 | ||
| 0.35 | 0.56 | Rowan | Iowa 3 at Rowan | 1938 | 1980 | Spur route | ||
| 0.35[16] | 0.56 | Mallard | Iowa 17 near Mallard | 1938 | 1960 | Spur route | ||
| 0.33[16] | 0.53 | Iowa 175 near Radcliffe | Radcliffe | 1938 | 1961 | Spur route | ||
| 6.37[15] | 10.25 | Packwood | Iowa 1 near Packwood | 1938 | 1981 | Spur route; section in Packwood removed 1980 | ||
| Iowa 356 | 0.949 | 1.527 | Milford | West Okoboji | 2000 | 2003 | Former section of US 71 | |
| 0.59[19] | 0.95 | Blockton | Iowa 25 near Blockton | 1938 | 1964 | Spur route | ||
| 1.55 | 2.49 | Whittemore | US 18 / Iowa 15 near Whittemore | 1938 | 1980 | Spur route | ||
| 7.383 | 11.882 | Buckeye | Iowa 941 in Alden | 1938 | 2003 | Spur route | ||
| 0.64[19] | 1.03 | Iowa 5 near Newell | Newell | 1938 | 1964 | Spur route | ||
| 0.38[16] | 0.61 | Bayard | Iowa 25 near Bayard | 1938 | 1962 | Spur route | ||
| 1.17 | 1.88 | Macedonia | US 59 near Macedonia | 1938 | 1980 | Spur route | ||
| 5.469 | 8.802 | DeSoto National Wildlife Refuge | I-29 at Loveland | 1980 | 2003 | Park access road | ||
| 1.616 | 2.601 | Iowa 150 near Urbana | I-380 / Iowa 27 in Urbana | 1939 | 2003 | Spur route; formerly Iowa 92; rerouted to end at I-380 in 1984 | ||
| 6.140 | 9.881 | Iowa 76 near Waukon Junction | Harpers Ferry | 1938 | 2003 | Spur route; section north of the bridge in Harpers Ferry removed 1980 | ||
| 1.07 | 1.72 | Tracy | Iowa 964 near Tracy | 1939 | 1980 | Spur route; did not extend to relocated Iowa 92 when Iowa 92 was rerouted in 1978 | ||
| 0.51[19] | 0.82 | US 75 near Blencoe | Blencoe | 1939 | 1964 | Spur route | ||
| 6 | 9.7 | Nebraska border | US 275 in Council Bluffs | 1939 | 1941 | Replaced by US 275 | ||
| 3.39 | 5.46 | Rutland | US 169 near Humboldt | 1942 | 1980 | Spur route | ||
| 0.50[19] | 0.80 | Renwick | Iowa 60 near Renwick | 1939 | 1964 | Spur route | ||
| Iowa 368 | 0.140 | 0.225 | 200th Avenue northwest of Hartford | Dead end | 2002 | current | Former section of Iowa 5 | |
| 2 | 3.2 | Iowa 92 near Knoxville | Coal mine | 1939 | 1941 | Now County Road T17 | ||
| 5.54 | 8.92 | Iowa 2 near Moulton | Unionville | 1942 | 1980 | Spur route | ||
| 0.46 | 0.74 | Iowa 57 | Dike | 1939 | 1952 | Spur route | ||
| 3.265 | 5.255 | N-370 at Bellevue, Neb. | I-29 / US 275 near Council Bluffs | 1953 | 2014 | Originally ended at US 275 (pre-2003 route); decommissioned in 1980, but restored west of I-29 in 1983 | ||
| 0.715 | 1.151 | Lake Keomah State Park | Iowa 92 near Keomah Village | 1939 | 2003 | Park access road | ||
| 2.60[5] | 4.18 | Preparation Canyon State Park | Iowa 183 near Moorhead | 1939 | 1968 | Park access road | ||
| 4.05[19] | 6.52 | Iowa 13 near Waterville | Waterville | 1942 | 1964 | Spur route | ||
| Iowa 373 | 2.307 | 3.713 | — | — | 2002 | 2003 | Former section of US 61 just southwest of Muscatine | |
| 7.99 | 12.86 | US 71 near Sioux Rapids | Webb | 1942 | 1980 | Spur route | ||
| Iowa 374 | 3.6[30] | 5.8 | Iowa 163 in Monroe | Dead end in Monroe | 2000 | 2000 | Former section of Iowa 163 | |
| 2.95[13] | 4.75 | US 6 in Council Bluffs | US 275 / Iowa 92 in Council Bluffs | 1941 | 1971 | Now 4th Street, 9th Avenue, 3rd Street, and Harry Langdon Boulevard | ||
| 0.46[5] | 0.74 | Iowa 3 near Colesburg | Colesburg | 1942 | 1965 | Spur route | ||
| Iowa 376 | 10.334 | 16.631 | I-129 / US 20 / US 75 at Sioux City | US 75 at Sioux City | 2001 | current | US 75 Business in Sioux City | |
| 0.55 | 0.89 | Harbor Drive in Sioux City | Iowa 970 in Sergeant Bluff | 1942 | 1980 | Airport access road | ||
| 2.13[22] | 3.43 | Harbor Drive in Sioux City | Iowa 475 (later Iowa 970) in Sergeant Bluff | 1942 | 1974 | Airport access road | ||
| 4.59 | 7.39 | Joice | Iowa 105 near Lake Mills | 1942 | 1980 | Spur route | ||
| 1.30[11] | 2.09 | Ottumwa Regional Airport | US 63 near Ottumwa | 1943 | 1969 | Renumbered Iowa 389 when I-380 was designated | ||
| 1.10[23] | 1.77 | Iowa 84 near Cedar Rapids | US 218 (now Club Road) near Cedar Rapids | 1943 | 1953 | Airport access road; now Wright Brothers Boulevard | ||
| 0.67 | 1.08 | Iowa 254 near Rake | Rake | 1954 | 1980 | Spur route | ||
| 4.792 | 7.712 | Lake MacBride State Park | Iowa 1 in Solon | 1943 | 2003 | Park access road | ||
| 1.311 | 2.110 | US 69 near Randall | Randall | 1944 | 2003 | Spur route | ||
| 1.231 | 1.981 | Iowa 25 in Guthrie County | Springbrook State Park | 1944 | 2003 | Park access road | ||
| 3.151 | 5.071 | Pacific Junction | US 34 / US 275 in Glenwood | 1945 | 2003 | Spur route | ||
| 2.685 | 4.321 | US 52 / Iowa 3 near Sageville | US 52 / Iowa 3 / Iowa 32 near Dubuque | 1946 | 2003 | |||
| 1.04[31] | 1.67 | US 65 near Zearing | Zearing | 1946 | 1950 | Spur route; replaced by an extended Iowa 317 | ||
| 0.52 | 0.84 | Davenport Municipal Airport | US 61 3 miles north of Davenport | 1951 | 1979 | Airport access road | ||
| 0.35 | 0.56 | Calumet | US 59 at Calumet | 1946 | 1980 | Spur route | ||
| 0.82[16] | 1.32 | Wild Cat Den State Park | Iowa 22 | 1946 | 1962 | Park access road | ||
| 1.25[9] | 2.01 | Ottumwa Regional Airport | US 63 near Ottumwa | 1969 | 1997 | Decommissioned when the first section of Ottumwa bypass opened | ||
| 0.74[7] | 1.19 | Marathon | Iowa 10 near Marathon | 1946 | 1980 | Spur route | ||
| Iowa 390 | 2.113 | 3.401 | South of Plainfield | North of Plainfield | 2002 | 2003 | Former section of US 218 | |
| 0.50[13] | 0.80 | Clinton Municipal Airport | US 30 near Clinton | 1946 | 1972 | Airport access road; now 60th Street | ||
| 0.63[22] | 1.01 | Dubuque Regional Airport | US 61 near Dubuque | 1946 | 1974 | Airport access road; now Airport Road | ||
| Iowa 392 | 3.09[29] | 4.97 | Iowa 163 in Prairie City | Iowa 163 in Prairie City | 1998 | 2000 | Former section of Iowa 163 | |
| 2.40 | 3.86 | Ionia | US 18 near Ionia | 1948 | 1980 | Spur route | ||
| 2.27 | 3.65 | Iowa 2 near Denmark | Iowa Army Ammunition Plant southern entrance | 1948 | 1980 | Spur route | ||
| 10.454 | 16.824 | Route B at St. Francisville, Mo. | US 218 near Donnellson | 1980 | 2005 | Replaced by Iowa 27 | ||
| 0.53 | 0.85 | Iowa 330 near Melbourne | Melbourne | 1948 | 1983 | Spur route; section in Melbourne removed 1980 | ||
| 0.89[21] | 1.43 | Iowa 14 in Newton | US 6 in Newton | 1948 | 1954 | Now 19th Avenue and 8th Street | ||
| 0.52 | 0.84 | Iowa 175 near Farnhamville | Farnhamville | 1954 | 1980 | Spur route | ||
| 0.69[17] | 1.11 | Paton | Iowa 144 near Paton | 1948 | 1991 | Spur route | ||
| 1.24 | 2.00 | Brooklyn | US 6 near Brooklyn | 1956 | 1980 | Spur route | ||
| 0.65[19] | 1.05 | Iowa 74 near Palo | Palo | 1956 | 1964 | Spur route | ||
| 4.54 | 7.31 | Truro | I-35 near Truro | 1957 | 1980 | Spur route; not completed until 1958 | ||
| 5.32[17] | 8.56 | Camp Dodge | US 6 in Des Moines | 1958 | 1991 | Replaced by an extended Iowa 28 south of I-80; rest decommissioned | ||
| 20.9 | 33.6 | Iowa 8 near Dysart | Iowa 412 in Waterloo | 1957 | 1968 | Replaced by Iowa 21 | ||
| 0.70 | 1.13 | Cushing | US 20 near Cushing | 1958 | 1980 | Spur route | ||
| 0.477 | 0.768 | SD 48 near Akron | Iowa 12 in Akron | 1980 | 2003 | |||
| 1.391 | 2.239 | Montrose | US 61 near Montrose | 1960 | 2003 | Spur route | ||
| Iowa 404 | 1.629 | 2.622 | Iowa 3 in Le Mars | US 75 at Le Mars | 2006 | current | Section of US 75 Business in Le Mars | |
| 0.249 | 0.401 | Lone Tree | Iowa 22 near Lone Tree | 1958 | 2003 | Spur route; section in Lone Tree removed 1980 | ||
| 2.275 | 3.661 | US 34 near West Burlington | Burlington | 1957 | 2003 | Formerly Iowa 80; spur route | ||
| 0.47[5] | 0.76 | Iowa 99 in Oakville | Oakville | 1957 | 1967 | Formerly Iowa 7; spur route | ||
| 7.40 | 11.91 | US 169 near Lu Verne | Lu Verne | 1957 | 1980 | Spur route | ||
| 0.41[5] | 0.66 | US 18 near Garner | Garner | 1957 | 1968 | Formerly Iowa 35; spur route | ||
| 2.157 | 3.471 | Backbone State Park | Iowa 3 / Iowa 13 near Strawberry Point | 1958 | 2003 | Park access road | ||
| 0.98[19] | 1.58 | US 6 at Marengo | CR F15 north of Marengo | 1957 | 1964 | Spur route | ||
| 4.72[14] | 7.60 | US 63 in Waterloo | US 218 in Waterloo | 1960 | 1983 | San Marnan Drive in Waterloo | ||
| 3.95[19] | 6.36 | US 20 in Fort Dodge | Fort Dodge Airport | 1960 | 1980 | Spur route; continued north to Iowa 320 near Badger until Iowa 320 was decommissioned | ||
| 6.12[13] | 9.85 | US 6 near Lewis | US 71 near Atlantic | 1958 | 1972 | Former section of Iowa 92; was Iowa 100 for a month in 1958 | ||
| 16.857 | 27.129 | US 6 in Des Moines | Iowa 141 near Granger | 1959 | current | |||
| 4.89[11] | 7.87 | Centralia | US 20 | 1959 | 1969 | Former section of US 20; sections were renumbered Iowa 418 and Iowa 420 in 1960 | ||
| Iowa 417 | 5.38[5] | 8.66 | US 67 near Riverdale | US 67 near LeClaire | 1960 | 1968 | Former section of US 67 | |
| 0.85[5] | 1.37 | Farley | US 20 | 1960 | 1968 | Former section of US 20 | ||
| 1.038 | 1.670 | Victor | US 6 / Iowa 21 near Victor | 1962 | 2003 | Spur route | ||
| 2.37[11] | 3.81 | Iowa 136 in Dyersville | US 20 | 1960 | 1969 | Former section of US 20 | ||
| Iowa 421 | 3.260 | 5.246 | — | — | 2000 | 2003 | Former section of US 61 northeast of Muscatine | |
| 0.52[18] | 0.84 | US 169 near Burt | Burt | 1964 | 1976 | Spur route; renumbered Iowa 969 | ||
| 0.44 | 0.71 | Iowa 111 in Britt | US 18 near Britt | 1961 | 1980 | Spur route | ||
| Iowa 424 | 2.802 | 4.509 | South of Swedesburg | US 218 near Olds | 1999 | 2003 | Former section of US 218 | |
| 0.52 | 0.84 | Iowa 92 near Rose Hill | Rose Hill | 1960 | 1980 | Former section of Iowa 92 | ||
| 1.21 | 1.95 | Anamosa | US 151 near Anamosa | 1965 | 1980 | Spur route | ||
| 6.140 | 9.881 | Maquoketa Caves State Park | US 61 near Maquoketa | 1980 | 2003 | Park access road | ||
| Iowa 431 | 3.183[25] | 5.123 | US 218 near Waverly | Iowa 3 in Waverly | 1998 | 2001 | Section of US 218 Business in Waverly | |
| Iowa 431 | 1.920[32] | 3.090 | US 30 near Le Grand | 2004 | 2014 | Former section of US 30 | ||
| Iowa 432 | 1.9 | 3.1 | Iowa 163 in Oskaloosa | Iowa 92 in Oskaloosa | 1998 | 2003 | Former section of Iowa 163 | |
| Iowa 434 | 8.993[27] | 14.473 | US 34 in Danville | US 34 in West Burlington | 2005 | 2008 | Former section of US 34 | |
| Iowa 437 | 0.299[33] | 0.481 | Dead end near Iowa 137 in Eddyville | Dead end near Iowa 342 in Eddyville | 2005 | 2008 | Former section of Iowa 137; abandoned road | |
| Iowa 438 | 1.052 | 1.693 | US 34 / Iowa 163 at Mount Pleasant | US 218 / Iowa 27 at Mount Pleasant | 2003 | current | Section of US 218 Business in Mount Pleasant | |
| Iowa 450 | 0.268 | 0.431 | Iowa 10 at Alton | Iowa 60 at Alton | 2005 | current | 450th Street | |
| Iowa 460 | 7.240[27] | 11.652 | — | — | 2004 | 2007 | Former sections of US 218 and Iowa 394 in Donnellson and Argyle | |
| Iowa 461 | 10.750 | 17.300 | I-280 / US 61 at Davenport | I-80 / US 61 at Davenport | 2010 | current | US 61 Business in Davenport | |
| Iowa 463 | 2.3 | 3.7 | US 63 near Frederika | US 63 near Frederika | 2009 | 2010 | Former section of US 63 | |
| Iowa 470 | 0.695 | 1.118 | US 75 in Merrill | 2011 | current | Former section of US 75 | ||
| 11.160 | 17.960 | Iowa 175 near Lake View | US 20 / US 71 near Early | 2015 | current | Formerly US 71 in Sac County | ||
| Iowa 475 | 31.79[34] | 51.16 | Business US 75 in Sioux City | Iowa 175 in Onawa | 1969 | 1976 | Former section of US 75; renumbered Iowa 970 | |
| Iowa 478 | 0.755 | 1.215 | Iowa 24 in New Hampton | North of New Hampton | 2002 | 2003 | Former section of US 63 | |
| Iowa 903 | 0.13 | 0.21 | Just south of Iowa 163 near Leighton | 2011 | current | Former section of Iowa 163 | ||
| Iowa 904 | 4.737 | 7.623 | US 34 / Iowa 163 west of Fairfield | US 34 / Iowa 163 east of Fairfield | 2008 | 2011 | US 34 Business at Fairfield, did not count mileage within Fairfield city limits | |
| Iowa 906 | 4.009 | 6.452 | Iowa 192 in Council Bluffs | I-80 / US 6 near Council Bluffs | 2016 | 2023 | Formerly US 6 through Council Bluffs | |
| Iowa 912 | 0.22[29] | 0.35 | — | — | 1997 | 1999 | Former section of Iowa 141 | |
| Iowa 913 | 1.686[9] | 2.713 | — | — | 1996 | 1997 | Former section of US 61 | |
| Iowa 914 | 1.01[25] | 1.63 | Storm Lake city limit boundary | Iowa 7 in Storm Lake | 1996 | 2001 | Former section of US 71 | |
| Iowa 915 | .27[17] | 0.43 | Iowa 3 / Iowa 150 in Oelwein | Iowa 3 / Iowa 150 in Oelwein | 1986 | 1990 | Former section of Iowa 3/Iowa 150 concurrency | |
| Iowa 915 | 3.7[35] | 6.0 | — | — | 1993 | 1994 | Former section of Iowa 415 in Ankeny | |
| Iowa 915 | .580[9] | 0.933 | Iowa 5 in Albia | Iowa 5 in Albia | 1995 | 1997 | Former section of Iowa 5 | |
| Iowa 916 | 1.293 | 2.081 | Iowa 281 in Oelwein | Oelwein city limits | 1986 | 2003 | Originally ended at Iowa 915 in Oelwein; former section of Iowa 150 | |
| Iowa 917 | 0.149 | 0.240 | US 61 and Iowa 22 near Muscatine | Muscatine city limits | 1986 | 2003 | Former section of Iowa 22 | |
| Iowa 918 | 1.119 | 1.801 | Iowa 16 near Eldon | Iowa 16 in Eldon | 1984 | 2003 | Former section of Iowa 16; street signs said "Hwy 918" | |
| Iowa 919 | 0.39[36] | 0.63 | Iowa 363 in Urbana | Walnut Street in Urbana | 1984 | 1995 | Former section of Iowa 363; now Ash Street and Wood Street | |
| 12.560 | 20.213 | Center Point | Iowa 150 near Urbana | 1984 | 2003 | Former section of Iowa 150 | ||
| Iowa 921 | 11.75[12] | 18.91 | Iowa 920 in Center Point | Hiawatha | 1984 | 1985 | Former section of Iowa 150 | |
| Iowa 921 | 2.505 | 4.031 | US 6 / Iowa 1 in Iowa City | US 218 in Iowa City | 1985 | 2003 | Former section of US 218 | |
| Iowa 922 | 1.27[12] | 2.04 | US 61 in Muscatine | Iowa 22 in Muscatine | 1984 | 1986 | Former section of US 61; became part of an extended Iowa 38 | |
| Iowa 922 | 1.12 | 1.80 | Iowa 149 in North English | unnamed street in North English | 1987 | 1988 | Former section of Iowa 149 | |
| Iowa 922 | 8.862 | 14.262 | US 151 at Cedar Rapids | Iowa 100 in Cedar Rapids | 1989 | current | US 151 Business in Cedar Rapids | |
| Iowa 923 | 8.819 | 14.193 | — | — | 1982 | 2003 | Former section of US 218; had three sections | |
| Iowa 924 | 4.00[15] | 6.44 | Iowa 175 near Farnhamville | Webster–Greene County Line | 1980 | 1982 | Now County Road P29 | |
| Iowa 924 | 2.24[26] | 3.60 | US 52 in Dubuque | Dead end in Dubuque | 1983 | 1992 | Former section of US 61/US 151 concurrency | |
| Iowa 924 | 0.665 | 1.070 | US 61 near Montrose | Dead end in Montrose | 1994 | 2003 | Formerly Iowa 998; former section of US 61 | |
| 26.259 | 42.260 | I-80 / US 6 in Adair | US 6 near Dexter | 1980 | 2003 | Former section of US 6 | ||
| Iowa 926 | 3.18[20] | 5.12 | US 6 | Altoona east city limit boundary | 1980 | 1988 | Former section of US 6; originally continued east to Newton | |
| Iowa 926 | 3.147 | 5.065 | US 169 / US 20 Bus at Fort Dodge | US 169 at Fort Dodge | 1990 | 2014 | ||
| 19.017 | 30.605 | US 6 / Iowa 38 in Wilton | I-280 / US 6 near Davenport | 1980 | 2003 | Former section of US 6; was signed in 1989 | ||
| Iowa 928 | 20.168 | 32.457 | Iowa 17 near Webster City | CR D20 near Williams | 1980 | 2003 | Former section of US 20 | |
| Iowa 929 | 0.789 | 1.270 | Murray city limits | Maple Street in Murray | 1980 | 2003 | Former section of Iowa 152 | |
| Iowa 930 | 1.738 | 2.797 | US 30 near Ames | Boone–Story county line | 1972 | current | Former section of US 30 | |
| Iowa 931 | 1.2 | 1.9 | Iowa 13 in Coggon | Iowa 13 near Coggon | 1976 | 1978 | Former section of Iowa 13 | |
| 8.962 | 14.423 | I-35 in Ankeny | US 65 in Polk County | 1980 | 2003 | |||
| Iowa 932 | 0.193 | 0.311 | Ryan city limits | Iowa 13 in Ryan | 1976 | 2003 | Former section of Iowa 13 | |
| Iowa 933 | 0.74[14] | 1.19 | Iowa 141 in Perry | Iowa 141 in Perry | 1976 | 1984 | Former section of Iowa 141 | |
| Iowa 933 | 0.21[29] | 0.34 | — | — | 1985 | 1999 | Former section of Iowa 58 just south of US 20 | |
| Iowa 934 | 1.07[7] | 1.72 | US 61 near Burlington | US 61 near Burlington | 1976 | 1980 | Former section of US 61; now Memorial Park Road | |
| Iowa 934 | 1.14[17] | 1.83 | Dallas–Polk county line | I-35 in Des Moines | 1981 | 1989 | Former section of Iowa 90 | |
| Iowa 934 | 4.76[26] | 7.66 | US 20 near Moorland | US 169 in Fort Dodge | 1990 | 1991 | Former section of US 20 | |
| Iowa 934 | 0.19[37] | 0.31 | — | — | 1992 | 1994 | Former section of US 34 just east of Iowa 97, which is now County Road S56 | |
| Iowa 934 | 4.881 | 7.855 | Iowa 58 in Cedar Falls | US 63 in Waterloo | 1998 | 2016 | Was an unsigned highway | |
| Iowa 935 | 0.77[15] | 1.24 | — | — | 1976 | 1981 | Former section of US 34 parallel to Business US 34 in Burlington | |
| Iowa 935 | 1.492 | 2.401 | I-29 | Mills–Pottawattamie county line | 1982 | 2003 | Former section of Iowa 370 | |
| Iowa 936 | 0.087[36] | 0.140 | east city limits of West Burlington | west city limits of Burlington | 1976 | 1995 | Former section of Iowa 406 | |
| Iowa 936 | 0.275 | 0.443 | Iowa 92 near Ainsworth | Iowa 923 near Ainsworth | 1997 | 2003 | Former section of Iowa 92 | |
| Iowa 937 | 4.23[24] | 6.81 | Iowa 2 near Bloomfield | Iowa 2 near Bloomfield | 1976 | 1977 | Former section of Iowa 2 | |
| Iowa 937 | 0.460 | 0.740 | Iowa 141 near Perry | US 169 near Perry | 1977 | 2003 | Former section of Iowa 141 | |
| Iowa 938 | 1.57[7] | 2.53 | Iowa 947 near Manchester | Manchester Fish Hatchery | 1976 | 1980 | Former Iowa 116 | |
| Iowa 938 | 0.460 | 0.740 | Union Street in Unionville | Unionville south city limit boundary | 1980 | 2003 | Former section of Iowa 369 | |
| Iowa 939 | 6.76[7] | 10.88 | US 65 | Iowa 2 near Corydon | 1976 | 1980 | Former section of Iowa 2 | |
| Iowa 939 | 18.931 | 30.466 | Iowa 187 near Masonville | Black Hawk–Buchanan county line | 1980 | 2003 | Former section of US 20 | |
| Iowa 940 | 2.51[7] | 4.04 | — | — | 1976 | 1980 | Former sections of Iowa 2 at County Road S70, County Road T14, and in Centerville | |
| Iowa 940 | 0.081 | 0.130 | Tama–Benton county line near Belle Plaine | Iowa 21 near Belle Plaine | 1981 | 2003 | ||
| Iowa 941 | 2.99[7] | 4.81 | County Road J18 in Moravia | Iowa 5 near Moravia | 1976 | 1980 | Former section of Iowa 5 | |
| Iowa 941 | 6.38[12] | 10.27 | US 30 / US 218 in Cedar Rapids | US 30 / US 218 in Cedar Rapids | 1981 | 1987 | Former section of US 30/US 218 concurrency | |
| Iowa 941 | 1.12[17] | 1.80 | 5th Avenue Southwest in Epworth | Bierman Road in Epworth | 1988 | 1990 | Former section of US 20 | |
| Iowa 941 | 12.953 | 20.846 | I-35 near Williams | Iowa Falls city limits | 1991 | 2003 | Former section of US 20 | |
| Iowa 942 | 5.70[7] | 9.17 | Iowa 5 near Moravia | County Road J18 in Moravia | 1976 | 1980 | Former section of Iowa 5; had another section south of Albia | |
| Iowa 942 | 0.466 | 0.750 | Vine Street in Woodburn | Woodburn city limits | 1980 | 2003 | Former section of Iowa 104 | |
| Iowa 943 | 0.69[7] | 1.11 | — | — | 1974 | 1980 | Former section of Iowa 13 in Central City | |
| Iowa 943 | 0.43[20] | 0.69 | 1st Street in Galva | Galva city limits | 1980 | 1987 | Former section of Iowa 328 | |
| Iowa 943 | 0.48[17] | 0.77 | — | — | 1988 | 1990 | Former Iowa 12 ramp in Sioux City; road destroyed 1990s | |
| Iowa 943 | 1.82[36] | 2.93 | US 63 in Denver | US 63 in Denver | 1994 | 1995 | Former section of US 63 | |
| Iowa 944 | 0.99[7] | 1.59 | Iowa 13 in Manchester | Iowa 13 in Manchester | 1976 | 1980 | Former section of Iowa 13 | |
| Iowa 944 | 0.553 | 0.890 | US 61 / Iowa 2 in Fort Madison | Fort Madison city limits | 1980 | 2003 | Former section of Iowa 88 | |
| 4.599 | 7.401 | I-80 near Altoona | Iowa 931 in Polk County | 1980 | 2003 | |||
| Iowa 946 | 2.72[7] | 4.38 | Luana city limits | US 18 / US 52 in Monona | 1976 | 1980 | Former section of US 18/US 52 concurrency; had two sections separated by the city limits of Monona | |
| Iowa 946 | 0.07[17] | 0.11 | US 218 in St. Ansgar | Park Street in St. Ansgar | 1988 | 1989 | Former section of US 218 | |
| Iowa 946 | 0.927 | 1.492 | US 52 / US 61 / US 151 in Dubuque | US 52 / US 61 / US 151 in Dubuque | 1991 | current | Provides direct access between US 20 and US 52 / US 61 / US 151 | |
| Iowa 947 | 23.75[7] | 38.22 | Iowa 187 | Dyersville city limits | 1976 | 1981 | Former section of US 20 | |
| Iowa 947 | 0.45[12] | 0.72 | Zearing city limits | Pearl Street in Zearing | 1981 | 1986 | Former section of Iowa 317 | |
| Iowa 947 | 4.74[12] | 7.63 | Iowa 57 in Cedar Falls | Greenhill Road in Waterloo | 1989 | 1992 | Former section of US 218 | |
| Iowa 947 | 2.47[9] | 3.98 | Iowa 70 in Columbus Junction | Market Street in Columbus City | 1994 | 2003 | Former section of Iowa 70; only the 0.671 miles in Columbus City were left on December 1, 1997 | |
| Iowa 948 | 5.08[20] | 8.18 | DeWitt city limits | US 30 near DeWitt | 1975 | 1987 | Former section of US 30 | |
| Iowa 948 | .30[37] | 0.48 | US 61 / US 151 in Dubuque | Iowa 959 in Dubuque | 1992 | 1993 | Former section of US 61/US 151 concurrency | |
| Iowa 949 | 2.275 | 3.661 | Glenwood city limits | US 34 / US 275 near Glenwood | 1974 | 2003 | Formerly US 34 Business | |
| Iowa 950 | 3.45[37] | 5.55 | US 6 / US 65 in Altoona | iowa 163 in Pleasant Hill | 1980 | 1994 | Now 34th Avenue/56th Street | |
| Iowa 951 | 2.65[7] | 4.26 | US 34 west of Osceola | US 34 near Osceola | 1976 | 1980 | Former section of US 34 | |
| Iowa 951 | 3.15[37] | 5.07 | Carbon city limits | Iowa 148 | 1983 | 1993 | Former Section of Iowa 95 | |
| Iowa 952 | 1.8 | 2.9 | US 61 in Burlington | Central avenue in Burlington | 1976 | 1976 | Former section of US 34 | |
| Iowa 952 | 0.18[14] | 0.29 | — | — | 1978 | 1982 | Former section of US 67 north of Clinton | |
| Iowa 952 | 0.112 | 0.180 | US 151 near Cascade | Reiter Road near Cascade | 1992 | 2003 | Former section of US 151 | |
| Iowa 953 | 0.89[7] | 1.43 | Iowa 38 near Muscatine | Iowa 38 in Muscatine | 1976 | 1980 | Former section of Iowa 38 | |
| Iowa 953 | 0.08[37] | 0.13 | Iowa 149 in North English | Dead end in North English | 1988 | 1994 | Former section of Iowa 149 | |
| Iowa 953 | 1.0[37] | 1.6 | Iowa 5 in West Des Moines | Browns Woods Road in West Des Moines | 1995 | 1996 | Former section of Iowa 28 | |
| Iowa 954 | 0.773 | 1.244 | US 61 near Maquoketa | Maquoketa city limits | 1967 | 2003 | Former section of US 61; numbered 1976 | |
| Iowa 955 | 0.727 | 1.170 | US 61 near Key West | Iowa 963 (Military Road) in Key West | 1971 | 2003 | Former section of US 61 | |
| Iowa 956 | 16.776 | 26.998 | CR F55 at Davenport | US 61 north of DeWitt | 1976 | 2003 | Former section of US 61 | |
| Iowa 957 | 3.33[24] | 5.36 | US 63 near Bloomfield | US 63 near Bloomfield | 1976 | 1977 | Former section of US 63 | |
| Iowa 957 | 0.062 | 0.100 | — | — | 1988 | 2003 | Former section of Iowa 22 | |
| Iowa 958 | 1.610 | 2.591 | Ottumwa city limits | US 63 south of Ottumwa | 1965 | 2003 | Former section of US 63 | |
| Iowa 959 | 1.27[7] | 2.04 | US 65 / US 69 in Des Moines | Des Moines city limits | 1970 | 1981 | Former section of US 65/US 69 concurrency | |
| Iowa 959 | 1.29[37] | 2.08 | US 61 / US 151 in Dubuque | US 61 / US 151 & US 52 in Dubuque | 1992 | 1993 | Former section of US 61/US 151 concurrency | |
| Iowa 960 | 1.58[7] | 2.54 | Clarinda city limits | Iowa 2 near Clarinda | 1973 | 1982 | Former section of Iowa 2 | |
| Iowa 960 | 1.11[12] | 1.79 | — | — | 1982 | 1986 | Former section of US 61 | |
| Iowa 960 | 4.7 | 7.6 | — | — | 1993 | 1994 | Former section of US 61/US 218 concurrency north of Keokuk | |
| Iowa 960 | 1.016 | 1.635 | US 75 Business/Iowa 404 in Le Mars | Dead end in Le Mars | 2006 | 2007 | Former section of Iowa 60 | |
| Iowa 961 | 0.56[7] | 0.90 | Villisca city limits | US 71 near Villisca | 1976 | 1980 | Former section of US 71 | |
| Iowa 961 | 1.08[37] | 1.74 | US 61 / US 151 in Dubuque | US 20 in Dubuque (southbound), Iowa 946 in Dubuque (northbound) | 1991 | 1993 | Former section of US 151 and US 61 | |
| Iowa 961 | 0.50[36] | 0.80 | — | — | 1994 | 1996 | Former section of US 61 in Wever | |
| Iowa 961 | 3.613 | 5.815 | Iowa 2 in Fort Madison | US 61 at Fort Madison | 2011 | 2013 | Section of US 61 Business in Fort Madison | |
| Iowa 962 | 0.11[9] | 0.18 | US 218 near Ainsworth | County Road W64 near Ainsworth | 1994 | 1997 | Former section of US 218 | |
| Iowa 963 | 4.139 | 6.661 | US 151 near Key West | US 61 / US 151 in Dubuque | 1971 | 2003 | Former section of US 151 and US 61 | |
| Iowa 964 | 4.704[9] | 7.570 | Iowa 92 near Knoxville | Iowa 92 near Knoxville | 1977 | 1996 | Former section of Iowa 92 | |
| Iowa 965 | 3.29[7] | 5.29 | — | — | 1976 | 1980 | Former section of US 52 | |
| Iowa 965 | 0.519 | 0.835 | US 6 in Coralville | I-80 in Coralville | 1985 | current | Former section of US 218; extended to Cedar Rapids until 2003 | |
| Iowa 966 | 4.89 | 7.87 | Centralia | US 20 | 1976 | 1996 | Former Iowa 416, and before that, was a section of US 20 | |
| Iowa 967 | 0.037 | 0.060 | US 20 near Farley | Farley city limits | 1976 | 2003 | Former Iowa 418, and before that, was a section of US 20 | |
| Iowa 968 | 2.37[17] | 3.81 | Iowa 136 in Dyersville | US 20 | 1976 | 1989 | Former Iowa 420, and before that, was a section of US 20 | |
| Iowa 968 | 5.36[36] | 8.63 | Iowa 163 in Pella | Iowa 163 in Pella | 1993 | 1994 | Former section of Iowa 163 | |
| Iowa 969 | 0.52[7] | 0.84 | US 169 near Burt | Burt | 1976 | 1980 | Spur route; former Iowa 422 | |
| Iowa 969 | 4.0 | 6.4 | US 218 near Janesville | US 218 near Janesville | 1993 | 1994 | Former section of US 218 | |
| Iowa 970 | 31.79[7] | 51.16 | Business US 75 in Sioux City | Iowa 175 in Onawa | 1976 | 2003 | Former section of US 75 | |
| Iowa 971 | 10.78[7] | 17.35 | Iowa 2 | US 59 in Shenandoah | 1975 | 1979 | Former section of Iowa 2 | |
| Iowa 971 | 1.802[25] | 2.900 | US 69 in Lake Mills | Winnebago–Worth county line | 1993 | 2003 | Former section of Iowa 105; only 0.777 miles in Lake Mills were left in 2002 | |
| Iowa 972 | 2.00 | 3.22 | US 218 | Mount Pleasant city limits | 1969 | 1974 | Former section of US 218; renumbered Iowa 976 to avoid confusion with the other Iowa 972 | |
| Iowa 972 | 2.772 | 4.461 | I-29 / US 34 near Glenwood | Iowa 385 near Pacific Junction | 1974 | 1974 | Former section of US 34; renumbered Iowa 978 to avoid confusion with the other Iowa 972 | |
| Iowa 972 | 10.17[7] | 16.37 | Iowa 92 / US 169 in Winterset | US 169 | 1974 | 1980 | Former section of US 169 | |
| Iowa 972 | 1.877 | 3.021 | Northwood city limits | Northwood city limits | 1993 | 2003 | Former section of Iowa 105 | |
| Iowa 973 | 1.95[13] | 3.14 | I-29 in Council Bluffs | US 6 in Council Bluffs | 1969 | 1971 | Former section of US 75 | |
| Iowa 973 | 10.32[22] | 16.61 | US 71 near Atlantic | Iowa 148 in Anita | 1972 | 1973 | Former section of US 6; became part of an extended Iowa 83 | |
| Iowa 973 | 1.49[7] | 2.40 | Iowa 92 in Winterset | Iowa 972 in Winterset | 1976 | 1980 | Former section of Iowa 92 | |
| Iowa 973 | 0.65 | 1.05 | St. Ansgar city limits | US 218 in St. Ansgar | 1993 | 2001 | Former section of Iowa 105 | |
| Iowa 974 | 5.09[7] | 8.19 | O'Connor Road northwest of Mount Vernon | Mount Vernon city limits | 1965 | 1980 | Former section of Iowa 150 | |
| Iowa 975 | 1.33[18] | 2.14 | North city limits of Marengo | CR F15 north of Marengo | 1964 | 1974 | Former section of Iowa 411 | |
| Iowa 975 | 1.55[12] | 2.49 | Iowa 964 in Knoxville | Iowa 5 / Iowa 92 in Knoxville | 1978 | 1986 | Former section of Iowa 5/Iowa 92 concurrency | |
| Iowa 975 | 0.13 | 0.21 | — | — | 1995 | 1995 | Former section of US 275/Iowa 333 concurrency east of Hamburg | |
| Iowa 976 | 2.00[18] | 3.22 | US 218 | Mount Pleasant city limits | 1974 | 1980 | Former section of US 218; formerly Iowa 972 | |
| Iowa 976 | 0.22 | 0.35 | Marshalltown city limits | Governor Road east of Marshalltown | 1996 | 1997 | Former section of US 30 | |
| Iowa 976 | 0.879 | 1.415 | — | — | 1997 | 2003 | Former section of US 30 | |
| Iowa 977 | 2.007 | 3.230 | US 59 in Cherokee | Iowa 3 near Cherokee | 1962 | 2003 | Former section of Iowa 3 | |
| Iowa 978 | 2.77[19] | 4.46 | Iowa 44 in Whittemore | Iowa 358 in Whittemore | 1962 | 1965 | Former section of Iowa 358 | |
| Iowa 978 | 2.772 | 4.461 | I-29 / US 34 near Glenwood | Iowa 385 near Pacific Junction | 1974 | 2003 | Former section of US 34; formerly Iowa 972 | |
| Iowa 979 | 19.80[13] | 31.87 | Iowa City limits | Iowa 38 | 1961 | 2003 | Former section of Iowa 1 | |
| Iowa 980 | 0.77[7] | 1.24 | US 34 near Ottumwa | Ottumwa city limits | 1967 | 1980 | Former section of US 34; formerly US 34 Alternate | |
| Iowa 981 | 0.44[7] | 0.71 | Iowa 150 near Fayette | Fayette city limits | 1967 | 1980 | Former section of Iowa 150; formerly Iowa 991 | |
| Iowa 981 | 0.2 | 0.32 | US 34 (later Iowa 340) in Batavia | US 34 (later Iowa 340) in Batavia | 1995 | 1996 | Former section of US 34 | |
| Iowa 982 | 0.30[19] | 0.48 | Dubuque–Jones County Line | Iowa 136 near Cascade | 1961 | 1965 | Former section of Iowa 136 | |
| Iowa 982 | 27.787 | 44.719 | Smithland city limits | Sioux City city limits | 1967 | 2003 | Former section of Iowa 141; formerly Iowa 994 | |
| Iowa 983 | 0.99[19] | 1.59 | Iowa 989 | US 34 / Iowa 213 | 1961 | 1964 | Former section of Iowa 213 | |
| Iowa 983 | 0.81[7] | 1.30 | US 34 west of Chariton | US 34 east of Chariton | 1967 | 1980 | Former section of US 34; formerly Iowa 995 and Iowa 996; had a gap through Chariton | |
| Iowa 983 | 0.2 | 0.32 | Market Street in Carlisle | Dead end in Carlisle | 1998 | 1998 | Former section of Iowa 5 | |
| Iowa 984 | 2.24[15] | 3.60 | Bettendorf city limits | US 67 in Le Claire | 1968 | 1982 | Former section of Iowa 417 | |
| Iowa 985 | 1.00[19] | 1.61 | US 63 north of Oskaloosa | US 63 north of Oskaloosa | 1961 | 1965 | Former section of US 63; decommissioned by 1965 | |
| Iowa 985 | 7.66[22] | 12.33 | Sioux City limits | I-29 in Sioux City | 1969 | 1973 | Former section of Iowa 7 | |
| Iowa 985 | 1.927 | 3.101 | US 52 near Bellevue State Park | US 52 near Bellevue | 1980 | 2003 | Park access road; former section of US 52 | |
| Iowa 986 | 4.86[12] | 7.82 | Harrison–Monona county line | Iowa 301 in River Sioux | 1968 | 1986 | Former section of US 75 | |
| Iowa 987 | 4.45[19] | 7.16 | US 63 / Iowa 412 in Waterloo | Hudson city limits | 1961 | 1964 | Former section of US 63 | |
| Iowa 988 | 0.16[19] | 0.26 | Iowa 58 near Hudson | Hudson city limits | 1961 | 1964 | Former section of US 63 | |
| 2.312 | 3.721 | I-29 / I-680 near Crescent | Iowa 183 in Crescent | 1975 | 2003 | |||
| Iowa 989 | 17.76[19] | 28.58 | Albia city limits | US 34 near Ottumwa | 1961 | 1964 | Former section of US 34 | |
| Iowa 990 | 0.27[19] | 0.43 | Iowa 150 near Fayette | Fayette city limits | 1961 | 1965 | Former section of Iowa 150 | |
| Iowa 991 | 0.44[5] | 0.71 | Fayette city limits | Iowa 150 near Fayette | 1961 | 1967 | Former section of Iowa 150; renumbered Iowa 981 | |
| Iowa 992 | 8.81[19] | 14.18 | Wesley city limits | Britt city limits | 1961 | 1965 | Former section of US 18 | |
| Iowa 993 | 3.52[19] | 5.66 | US 18 near Wesley | Wesley city limits | 1961 | 1965 | Former section of US 18 | |
| Iowa 994 | 27.787[5] | 44.719 | Smithland city limits | Sioux City city limits | 1961 | 1967 | Former section of Iowa 141; renumbered Iowa 982 | |
| Iowa 995 | 0.56[5] | 0.90 | US 34 west of Chariton | Chariton city limits | 1961 | 1967 | Former section of US 34; renumbered Iowa 983 | |
| Iowa 996 | 0.23[18] | 0.37 | Chariton city limits | US 34 east of Chariton | 1961 | 1976 | Former section of US 34; became a second section of Iowa 983 | |
| Iowa 997 | 0.89[11] | 1.43 | US 169 / Iowa 5 near Fort Dodge | Fort Dodge city limits | 1961 | 1970 | Former section of Iowa 5 (now Iowa 7) | |
| Iowa 998 | 0.67[37] | 1.08 | US 61 near Montrose | Dead end in Montrose | 1961 | 1994 | Former section of US 61; renumbered Iowa 924 | |
| Iowa 999 | 2.22[7] | 3.57 | Spruce Street in College Springs | Iowa 333 near College Springs | 1961 | 1980 | Former section of Iowa 333 | |
| ||||||||
References
edit- ^ 2012 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. January 1, 2012. Retrieved November 6, 2013.
- ^ 2002 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. January 1, 2002. Retrieved September 3, 2019.
- ^ a b c d e f g h "U.S. Road Markers Soon to Replace Familiar Primary Road Signs on U.S. System in Iowa". Service Bulletin Oct–Nov–Dec 1925. XIII (10–11–12). Iowa State Highway Commission: 3. 1925.
- ^ a b c d e f g h i j k l m 1938 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission. September 26, 1938. Retrieved September 13, 2019.
- ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj 1965 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission. June 1966. Retrieved September 13, 2019.
- ^ a b c d e f g h i j 1956 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission. May 1957. Retrieved September 14, 2019.
- ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac 1978 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. December 31, 1978. Retrieved September 13, 2019.
- ^ a b c d e f g h i 1941 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission. April 30, 1942. Retrieved September 14, 2019.
- ^ a b c d e f g h 1996 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. August 1997. Retrieved September 3, 2019.
- ^ a b c d e f g h i j k 1934 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission. March 25, 1935. Retrieved September 13, 2019.
- ^ a b c d e f g h 1968 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission. March 1970. Retrieved September 13, 2019.
- ^ a b c d e f g h i j k l m 1984 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. August 1985. Retrieved September 3, 2019.
- ^ a b c d e f g h i j 1970 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission. July 1971. Retrieved September 13, 2019.
- ^ a b c d 1982 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. December 31, 1982. Retrieved September 3, 2019.
- ^ a b c d e f g h i 1980 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. December 31, 1980. Retrieved September 13, 2019.
- ^ a b c d e f g h i j k l m 1959 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission. June 1960. Retrieved September 14, 2019.
- ^ a b c d e f g h i j k l m n o p 1988 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. January 1, 1988. Retrieved September 3, 2019.
- ^ a b c d e f g h 1974 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission. May 1, 1976. Retrieved September 13, 2019.
- ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa 1962 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission. May 1963. Retrieved September 13, 2019.
- ^ a b c d e f 1986 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. 1987. Retrieved September 3, 2019.
- ^ a b c d 1953 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission. August 1954. Retrieved September 14, 2019.
- ^ a b c d e f g 1972 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission. April 1973. Retrieved September 13, 2019.
- ^ a b 1951 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission. January 1, 1951. Retrieved September 14, 2019.
- ^ a b c d 1976 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. December 31, 1976. Retrieved September 12, 2019.
- ^ a b c d e f g h i 2000 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. August 2001. Retrieved September 3, 2019.
- ^ a b c d 1990 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. 1991. Retrieved September 3, 2019.
- ^ a b c d 2006 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. January 1, 2006. Retrieved September 3, 2019.
- ^ 2003 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. January 1, 2003. Retrieved September 3, 2019.
- ^ a b c d 1998 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. 1999. Retrieved September 3, 2019.
- ^ "Primary Route Descriptions – Unsigned Iowa 374 in Jasper County". Iowa Department of Transportation. Retrieved September 3, 2019.
- ^ 1949 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa State Highway Commission. January 1951. Retrieved September 14, 2019.
- ^ 2004 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. January 1, 2004. Retrieved September 3, 2019.
- ^ 2008 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. January 1, 2008. Retrieved September 3, 2019.
- ^ "Primary Route Descriptions – Iowa 475 in Monona County". Iowa Department of Transportation. Retrieved September 3, 2019.
- ^ "Official Description Change: Unsigned Iowa 915, Polk County". Iowa Department of Transportation. July 24, 1996.
- ^ a b c d e 1994 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. August 1995. Retrieved September 3, 2019.
- ^ a b c d e f g h i 1992 Volume of Traffic on the Primary Road System of Iowa (PDF) (Report). Iowa Department of Transportation. 1993. Retrieved September 7, 2019.