# List of state highways in Iowa

State highways in the U.S. state of Iowa are owned and maintained by the Iowa Department of Transportation.

## State highways

| Number | Length (mi) | Length (km) | Southern or western terminus | Northern or eastern terminus | Formed | Removed | Notes |
| No. 1 | 236 | 380 | Missouri state line near Lamoni | Minnesota state line near Northwood | 01920-01-011920 | 01926-01-011926 | Jefferson Highway through Iowa; replaced by US 65 and US 69 |
| Iowa 1 | 119.268 | 191.943 | Iowa 2 south of Keosauqua | US 151 south of Anamosa | 01926-01-011926 | current | |
| Iowa 2 | 233.80 | 376.26 | US 6 near Lewis | IL 2 at Muscatine | 01920-01-011920 | 01939-01-011939 | Renumbered Iowa 92 (renumbering approved 1938) |
| Iowa 2 | 251.376 | 404.550 | N-2 at Nebraska City, Neb. | US 61 at Fort Madison | 01941-01-011941 | current | Formerly Iowa 3 |
| Iowa 3 | 267.07 | 429.81 | N-2 at Nebraska City, Neb. | IL 9 at Fort Madison | 01920-01-011920 | 01941-01-011941 | Renumbered Iowa 2 |
| Iowa 3 | 323.102 | 519.982 | SD 50 near Westfield | Northwest Arterial at Dubuque | 01945-01-011945 | current | Replaced part of Iowa 5, all of Iowa 221, and part of Iowa 10 |
| Iowa 4 | 29.70 | 47.80 | US 59 / Iowa 141 at Denison | Iowa 175 at Odebolt | 01920-01-011920 | 01968-12-311968 | Renumbered Iowa 39 |
| Iowa 4 | 146.343 | 235.516 | Iowa 44 in Panora | MN 4 near Estherville | 01969-01-011969 | current | Formerly Iowa 17 |
| Iowa 5 | 77.64 | 124.95 | Iowa 3 near Aurelia | US 169 at Fort Dodge | 01920-01-011920 | 01968-12-311968 | Renumbered Iowa 7 |
| Iowa 5 | 103.540 | 166.631 | Route 5 south of Cincinnati | I-35 near West Des Moines | 01969-01-011969 | current | Formerly portion of Iowa 60 |
| No. 6 | 369 | 594 | Nebraska state line at Council Bluffs | Illinois state line at Clinton | 01920-01-011920 | 01926-01-011926 | Lincoln Highway through Iowa; replaced by US 30 |
| Iowa 6 | 104 | 167 | Route 5 near Cincinnati | US 32 in Des Moines | 01926-01-011926 | 01931-01-011931 | Formerly No. 17 and No. 59; became part of Iowa 60 when US 6 extended into Iowa |
| Iowa 7 | 140.69 | 226.42 | US 6 at Council Bluffs | City US 6 in Des Moines | 01920-01-011920 | 01939-01-011939 | Replaced by an extended Iowa 64 |
| Iowa 7 | 0.47 | 0.76 | Iowa 99 in Oakville | Oakville | 01955-01-011955 | 01957-01-011957 | Renumbered Iowa 407; spur route |
| Iowa 7 | 24.18 | 38.91 | I-29 / US 77 in Sioux City | Iowa 3 near Brunsville | 01957-01-011957 | 01968-12-311968 | Formerly Iowa 29; portion became Iowa 985 |
| Iowa 7 | 73.661 | 118.546 | Iowa 3 near Aurelia | US 169 at Fort Dodge | 01969-01-011969 | current | Formerly Iowa 5 |
| No. 8 | 283 | 455 | No. 6 in Council Bluffs | Illinois state line at Burlington | 01920-01-011920 | 01926-01-011926 | Replaced by US 34 |
| Iowa 8 | 13.961 | 22.468 | US 63 in Traer | US 218 near Garrison | 01926-01-011926 | current | |
| Iowa 9 | 295.088 | 474.898 | SD 42 near Larchwood | WIS 82 at Lansing | 01920-01-011920 | current | |
| Iowa 10 | 104.512 | 168.196 | SD 46 near Hawarden | Iowa 4 at Havelock | 01920-01-011920 | current | |
| Iowa 11 | 96.60 | 155.46 | US 151 / Iowa 64 in Cedar Rapids | US 52 / Iowa 24 in Calmar | 01920-01-011920 | 01941-01-011941 | Replaced by Iowa 150, which was proposed to become part of US 150 |
| Iowa 12 | 46.274 | 74.471 | US 20 / US 75 at Sioux City | Iowa 10 in Hawarden | 01920-01-011920 | current | Signed as US 20 Bus through Sioux City |
| Iowa 13 | 85.235 | 137.172 | US 30 / US 151 near Bertram | US 52 near Froelich | 01920-01-011920 | current | |
| Iowa 14 | 187.838 | 302.296 | Iowa 2 at Corydon | US 18 / US 218 Bus in Charles City | 01920-01-011920 | current | |
| Iowa 15 | 111 | 179 | US 30 in Ames | Minnesota state line near Lake Mills | 01920-01-011920 | 01935-01-011935 | Replaced by US 69 |
| Iowa 15 | 14.92 | 24.01 | Iowa 137 at Eddyville | US 63 in Ottumwa | 01937-01-011937 | 01968-12-311968 | Renumbered Iowa 23 |
| Iowa 15 | 4.655 | 7.491 | Route 15 south of Milton | Iowa 2 at Milton | 01969-01-011969 | 02003-01-012003 | Formerly Iowa 23 |
| Iowa 15 | 63.578 | 102.319 | Iowa 3 near Pocahontas | MN 15 near Armstrong | 01969-01-011969 | current | Formerly Iowa 44 |
| Iowa 16 | 239 | 385 | Missouri state line near Redding | Minnesota state line near Ledyard | 01920-01-011920 | 01930-01-011930 | Replaced by US 169 |
| Iowa 16 | 65.488 | 105.393 | US 34 near Agency | US 61 at Wever | 01930-01-011930 | current | |
| Iowa 17 | 147.48 | 237.35 | Iowa 64 in Panora | MN 4 near Estherville | 01920-01-011920 | 01968-12-311968 | Renumbered Iowa 4 |
| Iowa 17 | 102.789 | 165.423 | Iowa 141 at Granger | US 18 near Wesley | 01969-01-011969 | current | Formerly portion of Iowa 60 |
| No. 18 | 148 | 238 | Missouri state line at Braddyville | No. 23 at Sac City | 01920-01-011920 | 01926-01-011926 | Replaced by US 71 |
| No. 19 | 302 | 486 | South Dakota state line near Inwood | Wisconsin state line at Lansing | 01920-01-011920 | 01926-01-011926 | East end truncated to US 75 for a month in 1926; replaced by US 18 |
| Iowa 19 | 2.44 | 3.93 | Backbone State Park | Iowa 3 / Iowa 13 near Strawberry Point | 01927-01-011927 | 01957-01-011957 | Renumbered Iowa 410 |
| No. 20 | 324 | 521 | Illinois state line at Keokuk | Minnesota state line near Burr Oak | 01920-01-011920 | 01926-01-011926 | Replaced by US 61 and US 55 |
| Iowa 21 | 115 | 185 | Minnesota state line near Allendorf | Iowa 141 near Denison | 01920-01-011920 | 01934-01-011934 | Replaced by Iowa 73 (proposed US 73) |
| Iowa 21 | 97.152 | 156.351 | Iowa 149 near Hedrick | US 20 / Iowa 27 at Waterloo | 01934-01-011934 | current | Formerly ended at Iowa 92; extended south in 1980 |
| No. 22 | 34 | 55 | No. 5 at Le Mars | Minnesota state line north of Rock Rapids | 01920-01-011920 | 01926-01-011926 | Replaced by US 75 |
| Iowa 22 | 97.905 | 157.563 | Iowa 21 near Thornburg | US 61 at Davenport | 01926-01-011926 | current | |
| No. 23 | 130 | 210 | South Dakota state line at Sioux City | No. 16 at Fort Dodge | 01920-01-011920 | 01926-01-011926 | Replaced by US 20 |
| Iowa 23 | 4.78 | 7.69 | Route 15 south of Milton | Iowa 2 at Milton | 01926-01-011926 | 01968-12-311968 | Formerly part of No. 11; renumbered Iowa 15 |
| Iowa 23 | 14.316 | 23.039 | US 63 in Ottumwa | Iowa 137 at Eddyville | 01969-01-011969 | 01997-01-011997 | Formerly Iowa 15; partially replaced by US 63 |
| Iowa 23 | 16.022 | 25.785 | Iowa 92 at Oskaloosa | Iowa 149 near Fremont | 01997-01-011997 | current | Formerly US 63 |
| Iowa 24 | 127 | 204 | US 71 near Lyman | US 63 in Oskaloosa | 01920-01-011920 | 01927-01-011927 | Replaced by an extended Iowa 2 |
| Iowa 24 | 27.546 | 44.331 | US 18 / US 63 in New Hampton | US 52 / Iowa 150 in Calmar | 01928-01-011928 | current | |
| No. 25 | 20 | 32 | No. 15 / No. 24 at Winterset | No. 2 / No. 17 at Adel | 01920-01-011920 | 01926-01-011926 | Replaced by relocated Iowa 16 |
| Iowa 25 | 103.419 | 166.437 | Iowa 2 near Benton | US 30 near Scranton | 01926-01-011926 | current | Continued south to the Missouri state line until 1978, and to Blockton until 1980 |
| Iowa 26 | 10 | 16 | US 18 near Rock Valley | US 18 near Rock Valley | 01920-01-011920 | 01930-01-011930 | Replaced by relocated US 18 (portions were cancelled in exchange for relocated US 18) |
| Iowa 26 | 9.52 | 15.32 | US 18 in Inwood | Iowa 9 near Larchwood | 01930-01-011930 | 01968-12-311968 | Renumbered Iowa 182 |
| Iowa 26 | 11.370 | 18.298 | Iowa 9 in Lansing | MN 26 at New Albin | 01969-01-011969 | current | Formerly Iowa 182 |
| Iowa 27 | 21.2 | 34.1 | Iowa 12 in Akron | US 75 in Le Mars | 01920-01-011920 | 01929-01-011929 | Replaced by an extended Iowa 5 |
| Iowa 27 | 11 | 18 | Nebraska border | US 30 / US 75 in Missouri Valley | 01929-01-011929 | 01930-01-011930 | Renumbered Iowa 130 |
| Iowa 27 | 6.86 | 11.04 | Alvord | US 75 near Rock Rapids | 01930-01-011930 | 01980-01-011980 | Spur route; originally from US 75 to George |
| Iowa 27 | 281.689 | 453.335 | Route 27 near Wayland, Mo. | I-35 at the Minnesota state line | 02001-01-012001 | current | Avenue of the Saints |
| No. 28 | 72 | 116 | No. 6 / No. 11 in Cedar Rapids | No. 5 / No. 20 in Dubuque | 01920-01-011920 | 01926-01-011926 | Replaced by US 161 |
| Iowa 28 | 21.613 | 34.783 | Iowa 92 at Martensdale | I-35 / I-80 at Johnston | 01926-01-011926 | current | Previously ended at Iowa 5; extended to US 6 in 1980, and to I-80 in 1991 |
| Iowa 29 | 22.06 | 35.50 | I-29 / US 77 in Sioux City | Iowa 3 near Brunsville | 01920-01-011920 | 01957-01-011957 | Renumbered Iowa 7 when I-29 was designated |
| No. 30 | 25 | 40 | No. 23 at Moville | No. 5 at Remsen | 01920-01-011920 | 01926-01-011926 | Renumbered Iowa 140 |
| Iowa 31 | 38.504 | 61.966 | US 59 near Quimby | Iowa 141 near Smithland | 01920-01-011920 | current | |
| No. 32 | 5 | 8.0 | No. 5 near Cleghorn | Cleghorn | 01920-01-011920 | 01926-01-011926 | Renumbered Iowa 145 |
| Iowa 32 | 7.68 | 12.36 | Iowa 9 near Spirit Lake | US 71 near Milford | 01934-01-011934 | 01981-01-011981 | extended and renumbered Iowa 86 to match Minnesota |
| Iowa 32 | 5.101 | 8.209 | US 20 at Dubuque | US 52 / Iowa 3 at Sageville | 01995-01-011995 | 02021-01-012021 | Turned over to Dubuque after the US 52 Southwest Arterial opened |
| Iowa 33 | 3.4 | 5.5 | Meriden | Iowa 5 | 01920-01-011920 | 01930-01-011930 | Became a county road (now L51) due to rerouting of Iowa 5 between Iowa 143 and Cherokee |
| Iowa 33 | 55.95 | 90.04 | US 75 at Le Mars | MN 60 at Bigelow, Minn. | 01930-01-011930 | 01968-12-311968 | Renumbered Iowa 60 |
| No. 34 | 68 | 109 | No. 4 at Denison | No. 12 at Sioux City | 01920-01-011920 | 01926-01-011926 | Renumbered Iowa 141 |
| Iowa 35 | 49.00 | 78.86 | Iowa 37 near Turin | US 71 near Odebolt | 01920-01-011920 | 01948-01-011948 | Replaced by an extended Iowa 175 |
| Iowa 35 | 0.23 | 0.37 | US 18 near Garner | Garner | 01954-01-011954 | 01957-01-011957 | Spur route; renumbered Iowa 409 when I-35 was designated |
| Iowa 36 | 2.983 | 4.801 | Wall Lake | US 71 near Wall Lake | 01920-01-011920 | 02003-01-012003 | Spur route; now County Roads M64 (north-south section) and D59 (east-west section) |
| Iowa 37 | 40.321 | 64.890 | Iowa 175 near Turin | US 59 near Earling | 01920-01-011920 | current | Continued east to Irwin until 1982 |
| Iowa 38 | 98.941 | 159.230 | US 61 Bus / Iowa 92 in Muscatine | Iowa 3 near Edgewood | 01920-01-011920 | current | |
| Iowa 39 | 11.68 | 18.80 | US 30 near Logan | Iowa 64 / Iowa 191 at Portsmouth | 01920-01-011920 | 01968-12-311968 | Renumbered Iowa 44 |
| Iowa 39 | 24.321 | 39.141 | US 59 at Denison | Iowa 175 at Odebolt | 01969-01-011969 | current | Formerly Iowa 4 |
| No. 40 | 262 | 422 | No. 20 in Keokuk | Minnesota state line near Mona | 01920-01-011920 | 01926-01-011926 | Replaced by US 161, US 20, US 30, and US 218; the entire route is now US 218 |
| Iowa 40 | 3.524 | 5.671 | Allerton | Iowa 2 near Corydon | 01926-01-011926 | 02003-01-012003 | Spur route; now County Road S26 |
| Iowa 41 | 1.827 | 2.940 | Malvern | US 34 near Malvern | 01920-01-011920 | 02003-01-012003 | Spur route; now County Road L63 |
| Iowa 42 | 4.18 | 6.73 | US 275 / Iowa 2 near Riverton | Riverton | 01920-01-011920 | 01980-12-011980 | Spur route; now County Road J46 |
| Iowa 43 | 1.75 | 2.82 | Ringsted | Iowa 15 near Ringsted | 01920-01-011920 | 01980-01-011980 | Spur route; now a local road and County Road A34 |
| Iowa 44 | 63.95 | 102.92 | Iowa 3 near Pocahontas | MN 15 near Armstrong | 01920-01-011920 | 01968-12-311968 | Renumbered Iowa 15 |
| Iowa 44 | 104.524 | 168.215 | US 30 near Logan | Iowa 141 at Grimes | 01969-01-011969 | current | Formerly Iowa 39 and Iowa 64 |
| Iowa 45 | 1.324 | 2.131 | Manilla | Iowa 141 near Manilla | 01920-01-011920 | 02003-01-012003 | Spur route; now County Road M65 |
| Iowa 46 | 64.84 | 104.35 | US 59 near Denison | Iowa 17 (now Iowa 144) in Perry | 01920-01-011920 | 01941-01-011941 | Originally a double spur route; replaced by an extended Iowa 141 |
| Iowa 46 | 4.34 | 6.98 | Iowa 90 in Des Moines | Iowa 28 (now Army Post Road) in Des Moines | 01942-01-011942 | 01950-01-011950 | Now 9th Street, Mulberry Street, and 7th Street |
| Iowa 46 | 6.57 | 10.57 | Iowa 5 near Avon | Iowa 163 in Des Moines | 01953-01-011953 | 01998-01-011998 | Now city streets |
| Iowa 47 | 13 | 21 | Iowa 287 in Farnhamville | US 169 near Harcourt | 01920-01-011920 | 01940-01-011940 | Spur route; replaced by an extended Iowa 175 |
| Iowa 47 | 0.82 | 1.32 | Iowa 14 near Allison | Allison | 01941-01-011941 | 01980-01-011980 | Spur route; now 7th Street |
| Iowa 48 | 47.919 | 77.118 | US 59 at Shenandoah | US 6 near Lewis | 01920-01-011920 | current | |
| Iowa 49 | 27.228 | 43.819 | Iowa 2 in Bedford | US 34 in Adams County | 01920-01-011920 | 02003-01-012003 | 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) |
| Iowa 50 | 7.135 | 11.483 | US 169 near Lehigh | Lehigh | 01920-01-011920 | 02003-01-012003 | Spur route; now County Road D43 |
| Iowa 51 | 11.007 | 17.714 | US 18 / US 52 at Postville | Iowa 9 near Waukon | 01920-01-011920 | current | |
| Iowa 52 | 7 | 11 | Elma | US 63 east of Elma | 01920-01-011920 | 01934-01-011934 | Spur route; renumbered Iowa 272 when US 52 extended into Iowa |
| No. 53 | 13 | 21 | No. 14 near Rockford | No. 19 near Nora Springs | 01920-01-011920 | 01926-01-011926 | Renumbered Iowa 147 to avoid conflict with US 53 (which became US 55 in the revised numbering plan; see below) |
| Iowa 53 | 3.04 | 4.89 | Iowa 3 near Clarksville | Clarksville | 01926-01-011926 | 01949-01-011949 | Formerly No. 55; became part of Iowa 188 |
| Iowa 53 | 1.43 | 2.30 | Gowrie | Iowa 175 near Gowrie | 01953-01-011953 | 01969-01-011969 | Spur route; now local roads (Market and 4th Streets) |
| Iowa 54 | 2.99 | 4.81 | Marble Rock | Iowa 14 in Floyd County | 01920-01-011920 | 01980-01-011980 | Spur route; now County Road B60 |
| No. 55 | 3 | 4.8 | No. 10 near Clarksville | Clarksville | 01920-01-011920 | 01926-01-011926 | Renumbered Iowa 53 to avoid conflict with US 55 |
| Iowa 55 | 4.506 | 7.252 | Seymour | Iowa 2 near Promise City | 01934-01-011934 | 02003-01-012003 | Spur route; now County Road S60 |
| Iowa 56 | 24.432 | 39.319 | Iowa 150 at West Union | Iowa 13 at Elkader | 01920-01-011920 | current | |
| Iowa 57 | 18.41 | 29.63 | Iowa 14 near Fern | Iowa 58 in Cedar Falls | 01920-01-011920 | 01986-01-011986 | Section from Iowa 58 to US 20 was deleted in 1980; removed after US 20 freeway was constructed |
| Iowa 57 | 43.765 | 70.433 | US 65 near Iowa Falls | US 218 / Iowa 27 / Iowa 58 at Cedar Falls | 01986-01-011986 | current | Formerly US 20 |
| Iowa 58 | 12.030 | 19.360 | US 63 at Hudson | US 218 / Iowa 27 / Iowa 57 at Cedar Falls | 01920-01-011920 | current | |
| Iowa 59 | 197 | 317 | Minnesota state line | Iowa 5 at Albia | 01920-01-011920 | 01934-01-011934 | Replaced by US 63 and Iowa 137 |
| Iowa 60 | 233.24 | 375.36 | Route 5 south of Cincinnati | US 18 near Wesley | 01920-01-011920 | 01968-12-311968 | Renumbered Iowa 5 and Iowa 17 |
| Iowa 60 | 58.771 | 94.583 | US 75 at Le Mars | MN 60 at Bigelow, Minn. | 01969-01-011969 | current | Formerly Iowa 33 |
| No. 61 | 73 | 117 | No. 28 at Anamosa | No. 6 in Lyons | 01920-01-011920 | 01926-01-011926 | Renumbered Iowa 117 and Iowa 136 |
| Iowa 62 | 19.633 | 31.596 | Iowa 64 at Maquoketa | US 52 in Bellevue | 01920-01-011920 | current | |
| No. 63 | 24 | 39 | No. 59 in New Sharon | No. 7 in Grinnell | 01920-01-011920 | 01926-01-011926 | Renumbered Iowa 146 |
| Iowa 64 | 32 | 51 | Iowa 163 at Prairie City | US 30 in Colo | 01920-01-011920 | 01936-01-011936 | Renumbered Iowa 117 |
| Iowa 64 | 64.355 | 103.569 | US 151 at Anamosa | US 52 / IL 64 at Savanna, Ill. | 01939-06-201939 | current | Formerly Iowa 117 |
| No. 65 | 21 | 34 | No. 8 at Lucas | No. 1 south of Indianola | 01920-01-011920 | 01926-01-011926 | Renumbered Iowa 137 |
| Iowa 66 | 7 | 11 | Humeston | Iowa 3 near Humeston | 01920-01-011920 | 01930-01-011930 | Spur route; replaced by an extended Iowa 137 |
| Iowa 66 | 7.011 | 11.283 | Iowa 2 near Diagonal | Diagonal | 01930-01-011930 | 02003-01-012003 | Spur route; now County Road P33 |
| Iowa 67 | 6 | 9.7 | Seymour | Iowa 3 near Promise City | 01920-01-011920 | 01934-01-011934 | Spur route; renumbered Iowa 55 when US 67 extended into Iowa |
| Iowa 68 | 1.933 | 3.111 | Melrose | US 34 near Melrose | 01920-01-011920 | 02003-01-012003 | Spur route; now County Road S70 |
| No. 69 | 3 | 4.8 | No. 3 near Mystic | Mystic | 01920-01-011920 | 01926-01-011926 | Renumbered Iowa 138 |
| Iowa 70 | 8.20 | 13.20 | Macksburg | US 169 near Macksburg | 01920-01-011920 | 01966-01-011966 | Spur route; now County Road G41 |
| Iowa 70 | 23.954 | 38.550 | Iowa 92 at Columbus Junction | US 6 in West Liberty | 01969-01-011969 | current | Formerly Iowa 76 |
| No. 71 | 3 | 4.8 | Moulton | No. 3 near Moulton | 01920-01-011920 | 01926-01-011926 | Renumbered Iowa 142 |
| Iowa 72 | 10.89 | 17.53 | US 69 west of Dows | I-35 east of Dows | 01920-01-011920 | 01986-01-011986 | Originally a spur route; extended east from Dows to I-35 in 1980 |
| Iowa 73 | 35.9 | 57.8 | Iowa 8 in Dysart | US 6 in Marengo | 01920-01-011920 | 01934-01-011934 | Renumbered Iowa 212 to avoid conflict with new Iowa 73, which was proposed to become part of US 73 |
| Iowa 73 | 225 | 362 | Missouri state line south of Shenandoah | Minnesota state line near Allendorf | 01934-01-011934 | 01935-01-011935 | Was proposed to become part of US 73; replaced by US 59 |
| Iowa 73 | 14.97 | 24.09 | Iowa 141 in Coon Rapids | Iowa 44 | 01936-01-011936 | 01972-01-011972 | Became County Road N46 |
| Iowa 74 | 38.27 | 61.59 | Iowa 38 in Tipton | US 61 in Davenport | 01920-01-011920 | 01941-01-011941 | Replaced by Iowa 150, which was proposed to become part of US 150 |
| Iowa 74 | 11.168 | 17.973 | US 151 in Cedar Rapids | Palo | 01943-01-011943 | 01966-01-011966 | Spur route; renumbred Iowa 94 when I-74 was designated |
| No. 75 | 2 | 3.2 | No. 5 near Marcus | Marcus | 01920-01-011920 | 01926-01-011926 | Renumbered Iowa 143 |
| Iowa 76 | 25.98 | 41.81 | Columbus City | US 6 in West Liberty | 01920-01-011920 | 01968-12-311968 | Renumbered Iowa 70 |
| Iowa 76 | 48.911 | 78.715 | US 18 near McGregor | MN 76 near Eitzen, Minn. | 01969-01-011969 | current | Formerly portion of Iowa 13 |
| Iowa 77 | 2.685 | 4.321 | Iowa 92 near Keota | Keota | 01920-01-011920 | 02003-01-012003 | Spur route, continued south to Iowa 78 until 1980; now County Road W15 and a local road |
| Iowa 78 | 58.429 | 94.032 | Iowa 149 near Martinsburg | US 61 near Morning Sun | 01920-01-011920 | current | |
| Iowa 79 | 1.84 | 2.96 | Iowa 2 near Bonaparte | Bonaparte | 01920-01-011920 | 01980-01-011980 | Spur route; now County Road W40 |
| Iowa 79 | 5.637 | 9.072 | Geode State Park | US 34 in Middletown | 01980-01-011980 | 02003-01-012003 | 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 |
| Iowa 80 | 4.00 | 6.44 | US 34 near West Burlington | US 61 in Burlington | 01920-01-011920 | 01957-01-011957 | Spur route; renumbered Iowa 406 when I-80 was designated |
| Iowa 81 | 9.20 | 14.81 | Iowa 92 near West Chester | Iowa 22 at Wellman | 01920-01-011920 | 01968-12-311968 | Renumbered Iowa 114 |
| Iowa 81 | 2.215 | 3.565 | Route 81 near Farmington | Iowa 2 near Farmington | 01969-01-011969 | current | Formerly Iowa 114 |
| Iowa 82 | 3.773 | 6.072 | Blairstown | US 30 near Blairstown | 01920-01-011920 | 02003-01-012003 | Spur route; now County Road V66 |
| Iowa 83 | 34.191 | 55.025 | US 59 in Avoca | Iowa 148 in Anita | 01920-01-011920 | current | Continued west to Neola until 2003 |
| Iowa 84 | 6.09 | 9.80 | College Springs | US 71 near Shambaugh | 01920-01-011920 | 01943-01-011943 | Spur route; replaced by an extended Iowa 333 |
| Iowa 84 | 2.13 | 3.43 | Eastern Iowa Airport | I-380 near Cedar Rapids | 01943-01-011943 | 01980-01-011980 | Airport access road; now County Road E70 |
| Iowa 85 | 8.408 | 13.531 | Montezuma city limits | Iowa 21 near Deep River | 01920-01-011920 | current | |
| Iowa 86 | 4 | 6.4 | US 34 in Council Bluffs | Lake Manawa | 01920-01-011920 | 01928-01-011928 | Spur route; restored in 1931 as Iowa 241, later Iowa 192 |
| Iowa 86 | 3.7 | 6.0 | US 61 (now Sunnyside Avenue) in Burlington | US 61 (now Summer Street) in Burlington | 01929-01-011929 | 01945-01-011945 | Now Roosevelt Avenue and West Avenue |
| Iowa 86 | 0.47 | 0.76 | Fertile | Iowa 9 at Fertile | 01945-01-011945 | 01980-01-011980 | Spur route |
| Iowa 86 | 12.519 | 20.147 | US 71 near Milford | MN 86 near Spirit Lake | 01980-01-011980 | current | |
| Iowa 87 | 4.06 | 6.53 | US 69 west of Elkhart | Elkhart | 01920-01-011920 | 01983-01-011983 | Spur route |
| Iowa 88 | 37.65 | 60.59 | US 6 in Altoona | US 30 near Marshalltown | 01920-01-011920 | 01939-01-011939 | Originally a spur route; replaced by an extended Iowa 64 |
| Iowa 88 | 8.01 | 12.89 | US 61 / Iowa 2 in Fort Madison | Iowa 16 in Denmark | 01940-01-011940 | 01980-01-011980 | Originally a spur route |
| Iowa 89 | 25.87 | 41.63 | US 169 near Bouton | Iowa 64 in Johnston | 01920-01-011920 | 01941-01-011941 | Originally a spur route; replaced by an extended Iowa 141 |
| Iowa 89 | 7.69 | 12.38 | Iowa 141 near Woodward | Iowa 17 in Madrid | 01946-01-011946 | 01980-11-011980 | Replaced by an extended Iowa 210 |
| No. 90 | 40 | 64 | No. 17 near Bouton | No. 16 at Harcourt | 01920-01-011920 | 01926-01-011926 | Replaced by relocated Iowa 16 (now US 169) |
| Iowa 90 | 16 | 26 | Iowa 14 at Grundy Center | Iowa 59 near Voorhies | 01926-01-011926 | 01932-01-011932 | Formerly No. 58; became part of Iowa 58 again |
| Iowa 90 | 16.32 | 26.26 | I-80 in Dallas County | I-35 in Des Moines | 01932-01-011932 | 01981-01-011981 | Now County Road F90; section in Polk County maintained as unsigned Iowa 934 until 1989 |
| Iowa 91 | 2.69 | 4.33 | US 169 near Harcourt | Dayton | 01920-01-011920 | 01940-01-011940 | Spur route; replaced by an extended Iowa 175 |
| Iowa 91 | 4.18 | 6.73 | Ledyard | US 169 near Ledyard | 01940-01-011940 | 01980-05-011980 | Spur route; now County Road A30 |
| Iowa 91 | 4.643 | 7.472 | Iowa 9 in Lyon County | MN 91 at the Minnesota state line | 01980-01-011980 | 02003-01-012003 | Now County Road L14 (was K64 before 1980) |
| Iowa 92 | 1.33 | 2.14 | Iowa 101 near Urbana | Urbana | 01920-01-011920 | 01939-01-011939 | Spur route; became Iowa 363 |
| Iowa 92 | 274.231 | 441.332 | US 275 / N-92 in Council Bluffs | IL 92 at Muscatine | 01939-01-011939 | current | Formerly Iowa 2 |
| Iowa 93 | 29.534 | 47.530 | US 63 near Tripoli | Iowa 150 in Fayette | 01920-01-011920 | current | |
| Iowa 94 | 13.12 | 21.11 | US 151 in Marion | US 30 in Mount Vernon | 01920-01-011920 | 01958-01-011958 | Replaced by relocated Iowa 150 |
| Iowa 94 | 11.168 | 17.973 | US 151 Business in Cedar Rapids | Palo | 01966-01-011966 | 02003-01-012003 | Spur route; now County Road W36 in Linn County and city streets in Cedar Rapids |
| Iowa 95 | 6 | 9.7 | US 169 near Bouton | Woodward | 01920-01-011920 | 01932-01-011932 | Spur route; replaced by an extended Iowa 89 |
| Iowa 95 | 3.70 | 5.95 | Carbon | Iowa 148 north of Corning | 01932-01-011932 | 01983-01-011983 | Spur route; section inside Carbon eliminated 1980; rest redesignated as unsigned Iowa 951 |
| Iowa 96 | 16.635 | 26.771 | Iowa 14 near Gladbrook | US 63 near Gladbrook | 01920-01-011920 | current | |
| Iowa 97 | 1.532 | 2.466 | Russell | US 34 near Russell | 01920-01-011920 | 02003-01-012003 | Spur route; much of route now County Road S56 with the last two blocks now Shaw Street |
| Iowa 98 | 11.10 | 17.86 | US 34 near Agency | Selma | 01920-01-011920 | 01944-01-011944 | Spur route; replaced by an extended Iowa 16, and Iowa 98 was reassigned to the old route of Iowa 16 |
| Iowa 98 | 1.814 | 2.919 | Leando | Iowa 16 near Douds | 01920-01-011920 | 02017-01-012017 | 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 |
| Iowa 99 | 33 | 53 | US 30 near Camanche | US 61 in Davenport | 01920-01-011920 | 01931-01-011931 | Replaced by US 55 (later US 67) |
| Iowa 99 | 33.232 | 53.482 | US 34 in Burlington | US 61 in Wapello | 01931-01-011931 | 02003-01-012003 | Now County Road X99; was County Road 99 until 2005 |
| Iowa 100 | 44.42 | 71.49 | US 275 / Iowa 375 in Council Bluffs | US 71 in Lyman | 01920-01-011920 | 01958-01-011958 | 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 |
| Iowa 100 | 6.12 | 9.85 | US 6 near Lewis | US 71 near Atlantic | 01958-01-011958 | 01958-01-011958 | Former section of Iowa 92; renumbered Iowa 414 due to confusion with old Iowa 100 |
| Iowa 100 | 16.140 | 25.975 | US 30 / US 218 in Cedar Rapids | US 151 / Iowa 13 near Marion | 01984-01-011984 | current | Former portion of Iowa 150 |
| Iowa 101 | 15.56 | 25.04 | US 218 in Vinton | Iowa 150 north of Urbana | 01920-01-011920 | 01984-01-011984 | Replaced by a relocated Iowa 150 |
| Iowa 102 | 1.82 | 2.93 | Hawkeye | US 18 near Hawkeye | 01920-01-011920 | 01980-01-011980 | Now County Road W14 |
| Iowa 102 | 0.501 | 0.806 | New Sharon city limits | US 63 / Iowa 146 in New Sharon | 01980-01-011980 | current | Unsigned highway; formerly extended to Pella (this is now County Road G5T) |
| Iowa 103 | 15.649 | 25.185 | US 218 near Donnellson | US 61 / Iowa 2 in Fort Madison | 01920-01-011920 | 02003-01-012003 | Now County Road J40 |
| No. 104 | 20 | 32 | No. 8 near Council Bluffs | No. 4 in Macedonia | 01920-01-011920 | 01926-01-011926 | First highway to be decommissioned in Iowa; became a county road (now numbered G66) |
| Iowa 104 | 1.53 | 2.46 | Woodburn | US 34 near Woodburn | 01927-01-011927 | 01980-01-011980 | Spur route; now County Road R69; segment in Woodburn maintained as unsigned Iowa 942 until 2003 |
| Iowa 105 | 34.23 | 55.09 | US 69 in Lake Mills | US 218 in St. Ansgar | 01920-01-011920 | 01992-01-011992 | Section from US 69 to Winnebago–Worth county line last shows on 1994 map, so was signed until 1994; now County Road 105 |
| Iowa 106 | 8.98 | 14.45 | Iowa 107 in Clear Lake | US 65 in Mason City | 01920-01-011920 | 01980-01-011980 | Now local roads and County Road B35 |
| Iowa 107 | 27.579 | 44.384 | Iowa 3 near Alexander | CR B35 near Clear Lake | 01920-01-011920 | 02011-01-012011 | All but parts in Meservey and Thornton removed in 2003; now County Roads S25, B65 and S14 |
| Iowa 108 | 1.18 | 1.90 | Delta | Iowa 92 near Delta | 01923-01-011923 | 01980-01-011980 | Spur route; now County Road V33 and Iowa 21 |
| Iowa 109 | 1.268 | 2.041 | Oxford | US 6 near Oxford | 01923-01-011923 | 02003-01-012003 | Spur route; now County Road W38 |
| Iowa 110 | 0.7 | 1.1 | Larrabee | Iowa 73 in Larrabee | 01923-01-011923 | 01934-01-011934 | Spur route; decommissioned when Iowa 73 (proposed US 73, now US 59) was relocated to go through Larrabee; now a county road (455th Street) |
| Iowa 110 | 14.789 | 23.801 | US 20 at Schaller | Iowa 7 at Storm Lake | 01934-01-011934 | current | |
| Iowa 111 | 26.72 | 43.00 | Kanawha | Woden | 01923-01-011923 | 01990-01-011990 | Double spur route with US 18; originally a spur route; now County Road R35 |
| Iowa 112 | 3 | 4.8 | Iowa 13 | Edgewood | 01923-01-011923 | 01930-01-011930 | Spur route; replaced by an extended Iowa 10 (this section now Iowa 3) |
| Iowa 112 | 5.19 | 8.35 | Volga | Iowa 13 near Osborne | 01931-01-011931 | 01980-01-011980 | Spur route; now County Road C24 |
| Iowa 113 | 34.09 | 54.86 | Iowa 10 near Edgewood | US 151 in Monticello | 01924-01-011924 | 01938-01-011938 | Replaced by an extended Iowa 38 |
| Iowa 113 | 1.187 | 1.910 | Iowa 64 near Spragueville | Spragueville | 01938-01-011938 | 02003-01-012003 | Spur route; now County Road Z20 |
| Iowa 114 | 2.22 | 3.57 | Route 81 near Farmington | Iowa 2 near Farmington | 01923-01-011923 | 01968-12-311968 | Swapped with Iowa 81 |
| Iowa 114 | 9.20 | 14.81 | Iowa 92 near West Chester | Iowa 22 at Wellman | 01969-01-011969 | 01981-01-011981 | Formerly Iowa 81; now County Road W38 |
| Iowa 115 | 1.34 | 2.16 | US 69 | Story City | 01923-01-011923 | 01969-01-011969 | Spur route; now County Road E15 |
| Iowa 115 | 1.237 | 1.991 | US 34 near Stanton | Viking Lake State Park | 01980-01-011980 | 02003-01-012003 | Park access road; now County Roads M65 and H43 |
| Iowa 116 | 1.57 | 2.53 | US 20 near Manchester | Manchester Fish Hatchery | 01923-01-011923 | 01976-01-011976 | 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 | 01998-01-011998 | current | Section of US 218 Business in Waverly; signed as US 218 Business instead of Iowa 118 |
| Iowa 117 | 63 | 101 | US 161 at Anamosa | US 52 / IL 64 at Savanna, Ill. | 01923-01-011923 | 01936-01-011936 | Swapped with Iowa 64 |
| Iowa 117 | 18.562 | 29.873 | Iowa 163 at Prairie City | US 65 / Iowa 330 near Mingo | 01939-06-201939 | current | Formerly Iowa 64 |
| Iowa 118 | 4.06 | 6.53 | Steamboat Rock | Iowa 175 near Eldora | 01923-01-011923 | 01989-01-011989 | Spur route; now County Road S56 and a local road (Market Street) |
| Iowa 119 | 1.04 | 1.67 | Dorchester | Iowa 76 near Dorchester | 01923-01-011923 | 01980-01-011980 | Spur route; now County Road A16 |
| Iowa 120 | 0.80 | 1.29 | Stanton | US 34 near Stanton | 01924-01-011924 | 01980-01-011980 | Spur route; now County Road M63 |
| Iowa 121 | 0.51 | 0.82 | Dolliver Memorial State Park | Iowa 50 near Lehigh | 01924-01-011924 | 01964-01-011964 | Park access road; became a county road (now numbered D64) |
| Iowa 122 | 5.47 | 8.80 | Iowa 150 in Davenport | US 61 in Davenport | 01924-01-011924 | 01960-01-011960 | Now Pine Street, Cheyenne Avenue, Division Street, Locust Street, and Marquette Street |
| Iowa 122 | 3.04 | 4.89 | Iowa 3 near Clarksville | Clarksville | 01964-01-011964 | 01965-01-011965 | Former section of Iowa 188; became part of Iowa 188 again |
| Iowa 122 | 12.264 | 19.737 | I-35 / US 18 at Clear Lake | Mason City city limits | 01999-01-011999 | current | |
| Iowa 123 | 10.51 | 16.91 | I-35 in Des Moines | Iowa 90 in Des Moines | 01924-01-011924 | 01959-01-011959 | Partially replaced by Iowa 60; rest now Fleur Drive |
| Iowa 123 | 0.45 | 0.72 | US 34 near Rome | Rome | 01969-01-011969 | 01980-01-011980 | Spur route; inside Rome stayed in the highway system until 1981 |
| Iowa 124 | 2.567 | 4.131 | Iowa 4 in Calhoun County | Twin Lakes State Park | 01924-01-011924 | 02003-01-012003 | Park access road; now County Roads D26 and N57 |
| Iowa 125 | 3.26 | 5.25 | Salem | US 218 east of Salem | 01924-01-011924 | 01981-01-011981 | Spur route; section inside Salem deleted in 1980; now County Road J20 |
| Iowa 126 | 1.28 | 2.06 | US 6 near Mitchellville | Mitchellville | 01924-01-011924 | 01980-01-011980 | Spur route; now unsigned County Road S27 |
| Iowa 127 | 15.985 | 25.725 | I-29 near Mondamin | US 30 in Logan | 01924-01-011924 | current | |
| Iowa 128 | 6.982 | 11.236 | Iowa 13 near Elkader | US 52 near Garnavillo | 01924-01-011924 | current | |
| Iowa 129 | 0.45 | 0.72 | US 34 near Rome | Rome | 01924-01-011924 | 01969-01-011969 | Spur route; renumbered Iowa 123 when I-129 was designated |
| Iowa 130 | 12 | 19 | Iowa 9 near Cresco | Minnesota border near Harmony, Minn | 01925-01-011925 | 01930-01-011930 | Renumbered Iowa 139 so Iowa 130 could be reused as a spur of US 30 |
| Iowa 130 | 11 | 18 | Nebraska border | US 30 / US 75 in Missouri Valley | 01930-01-011930 | 01931-01-011931 | Formerly Iowa 27; replaced by relocated US 30 |
| Iowa 130 | 6.65 | 10.70 | Maquoketa Caves State Park | US 61 near Maquoketa | 01931-01-011931 | 01966-01-011966 | Park access road; became a county road (later numbered Y31); was Iowa 428 from 1980 to 2003 |
| Iowa 130 | 32.023 | 51.536 | Iowa 38 in Tipton | I-80 / US 61 at Davenport | 01969-01-011969 | current | Former section of Iowa 150 |
| Iowa 131 | 2 | 3.2 | US 20 near Holstein | US 59 near Holstein | 01925-01-011925 | 01937-01-011937 | Section from US 20 to Holstein replaced by realigned US 59; rest given to county because US 59 was realigned |
| Iowa 131 | 4.520 | 7.274 | Iowa 21 in Belle Plaine | US 30 near Belle Plaine | 01937-01-011937 | 02003-01-012003 | Part of the Lincoln Highway; now County Road V40 |
| Iowa 132 | 5.74 | 9.24 | I-35 / I-80 in Des Moines | Iowa 90 (now US 6) in Des Moines | 01925-01-011925 | 01963-01-011963 | Now Douglas Avenue |
| Iowa 133 | 4.23 | 6.81 | US 34 / US 218 in Mount Pleasant | Oakland Mills Park (then a state park) | 01925-01-011925 | 01961-01-011961 | Park access road; became a county road (now numbered H61) |
| Iowa 133 | 0.970 | 1.561 | US 30 in Nevada | Nevada | 01964-01-011964 | 02003-01-012003 | Spur route; now 6th Street |
| Iowa 134 | 7 | 11 | US 65 near Hubbard | Iowa 58 | 01925-01-011925 | 01930-01-011930 | Replaced by relocated Iowa 58 |
| Iowa 134 | 8 | 13 | Nebraska state line | US 34 / US 275 in Glenwood | 01930-01-011930 | 01935-01-011935 | Replaced by relocated US 34 |
| Iowa 134 | 4.06 | 6.53 | US 65 near Hampton | Geneva | 01935-01-011935 | 01980-01-011980 | Spur route; now County Road C47 |
| Iowa 134 | 1.75 | 2.82 | Beed's Lake State Park | Iowa 3 near Hampton | 01980-01-011980 | 01987-01-011987 | Park access road; now County Road S42 |
| Iowa 135 | 0.75 | 1.21 | US 30 near Le Grand | Le Grand | 01926-01-011926 | 01954-01-011954 | Spur route; replaced by relocated US 30; Iowa 135 on route shown below |
| Iowa 135 | 1.96 | 3.15 | Montour | US 30 near Montour | 01954-01-011954 | 01980-01-011980 | Spur route; now County Road T47 |
| Iowa 136 | 87.611 | 140.996 | IL 136 at Clinton | US 20 / US 52 at Dyersville | 01926-01-011926 | current | |
| Iowa 137 | 21 | 34 | US 34 at Lucas | US 65 near Indianola | 01926-01-011926 | 01934-01-011934 | Formerly No. 65; replaced by realigned US 65 |
| Iowa 137 | 14.526 | 23.377 | Iowa 5 at Albia | US 63 / Iowa 163 at Eddyville | 01934-01-011934 | current | Formerly Iowa 59 |
| Iowa 138 | 3.16 | 5.09 | Iowa 2 near Mystic | Mystic | 01926-01-011926 | 01973-01-011973 | Formerly No. 69; now County Road T14 |
| Iowa 139 | 21 | 34 | US 161 in Iowa City | Iowa 38 near Rochester | 01926-01-011926 | 01929-01-011929 | Formerly No. 74; replaced by an extended Iowa 1 |
| Iowa 139 | 11.431 | 18.396 | Iowa 9 near Cresco | MN 139 near Harmony, Minn | 01930-01-011930 | current | Formerly Iowa 130; continued south to Protivin from 1935 to 1980 |
| Iowa 140 | 25.309 | 40.731 | US 20 at Moville | Iowa 3 at Remsen | 01926-01-011926 | 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 |
| Iowa 141 | 155.362 | 250.031 | I-29 near Sloan | I-35 / I-80 at Grimes | 01926-01-011926 | current | |
| Iowa 142 | 10.50 | 16.90 | Route 202 at Coatsville, Mo | Iowa 2 near Moulton | 01926-01-011926 | 01968-12-311968 | Former Iowa 71; renumbered Iowa 202 |
| Iowa 142 | 20.901 | 33.637 | Iowa 2 in Plano | Iowa 5 near Moravia | 01980-01-011980 | 02003-01-012003 | Now County Roads S70 and J18 |
| Iowa 143 | 12.049 | 19.391 | Iowa 3 at Marcus | Iowa 10 at Granville | 01926-01-011926 | current | |
| Iowa 144 | 34.039 | 54.780 | Iowa 141 at Perry | Iowa 175 near Harcourt | 01926-01-011926 | current | |
| Iowa 145 | 5 | 8.0 | Iowa 5 near Cleghorn | Cleghorn | 01926-01-011926 | 01931-01-011931 | Formerly No. 32; became a county road (now numbered L40) |
| Iowa 145 | 7.408 | 11.922 | I-29 near Thurman | US 275 near Sidney | 01931-01-011931 | 02003-01-012003 | Originally a spur route west to Thurman; extended west in 1980; now County Road J24 |
| Iowa 146 | 42.735 | 68.775 | US 63 / Iowa 102 in New Sharon | US 30 in Le Grand | 01926-01-011926 | current | |
| Iowa 147 | 6.706 | 10.792 | Rockford | Iowa 14 in Floyd County | 01926-01-011926 | 02003-01-012003 | Spur route, former Iowa 53; now County Road B45 |
| Iowa 148 | 66.828 | 107.549 | Route 148 near Bedford | I-80 / US 6 near Anita | 01926-01-011926 | current | |
| Iowa 149 | 65.897 | 106.051 | US 34 in Ottumwa | I-80 near Williamsburg | 01926-01-011926 | current | Section from I-80 to US 6 removed 1985 |
| Iowa 150 | 19 | 31 | US 32 at Homestead | US 30 near Cedar Rapids | 01926-01-011926 | 01930-01-011930 | Formerly No. 13; replaced by an extended Iowa 149 |
| Iowa 150 | 10 | 16 | Schleswig | Iowa 141 near Denison | 01930-01-011930 | 01930-01-011930 | Replaced by an extended Iowa 21 |
| Iowa 150 | 22.96 | 36.95 | US 30 / Iowa 17 in Jefferson | Iowa 64 in Panora | 01931-01-011931 | 01941-01-011941 | Replaced by relocated Iowa 17 to avoid conflict with new Iowa 150, which was proposed to become part of US 150 |
| Iowa 150 | 85.093 | 136.944 | US 218 at Vinton | US 52 / Iowa 24 at Calmar | 01941-01-011941 | current | |
| Iowa 151 | 13 | 21 | US 71 at Auburn | Iowa 17 near Lake City | 01926-01-011926 | 01938-01-011938 | Formerly No. 35; renumbered Iowa 188 when US 151 extended into Iowa |
| Iowa 152 | 1.31 | 2.11 | US 34 near Murray | Murray | 01926-01-011926 | 01980-01-011980 | Formerly No. 8; now County Road R16 |
| Iowa 152 | 1.402 | 2.256 | I-35 near Osceola | US 69 at Osceola | 01980-01-011980 | 02014-01-012014 | Now County Road R35 |
| Iowa 153 | 7.0 | 11.3 | Iowa 117 in Wyoming | Oxford Junction | 01926-01-011926 | 01930-01-011930 | Replaced by an extended Iowa 136 |
| Iowa 153 | 4.82 | 7.76 | US 218 near North Liberty | US 6 near Coralville | 01930-01-011930 | 01957-01-011957 | Replaced by rerouted US 218 and local roads |
| Iowa 153 | 1.02 | 1.64 | US 218 near North Liberty | North Liberty | 01957-01-011957 | 01968-01-011968 | Former portion of US 218; now Dubuque Street |
| Iowa 154 | 12.82 | 20.63 | Iowa 150 near Fayette | Iowa 3 in Maryville | 01926-01-011926 | 01980-11-011980 | Replaced by Iowa 187 |
| Iowa 155 | 7.0 | 11.3 | Commerce | Iowa 28 (now 9th Street) in Des Moines | 01927-01-011927 | 01931-01-011931 | Spur route; now Walnut Woods Drive, Browns Woods Drive, and McKinley Avenue; parts of the road were destroyed |
| Iowa 155 | 3.05 | 4.91 | Nodaway | US 34 near Nodaway | 01933-01-011933 | 01980-10-011980 | Spur route; now County Road N26, 8th Avenue and 3rd Street |
| Iowa 156 | 4.748 | 7.641 | Iowa 5 near Marysville | Bussey | 01928-01-011928 | 02003-01-012003 | Spur route, section inside Bussey removed 1980; now County Road G71 |
| Iowa 157 | 0.15 | 0.24 | Monticello | US 161 near Monticello | 01928-01-011928 | 01931-01-011931 | Spur route; now Cedar Street; was the shortest state highway at the time |
| Iowa 157 | 1.032 | 1.661 | US 63 near Lime Springs | Lime Springs | 01931-01-011931 | 02003-01-012003 | Spur route; now County Road A21 |
| Iowa 158 | 0.65 | 1.05 | Iowa 60 near Carlisle | Carlisle | 01929-01-011929 | 01962-01-011962 | Spur route; now School Street |
| Iowa 159 | 1.83 | 2.95 | Iowa 92 near Harper | Harper | 01929-01-011929 | 01980-01-011980 | Spur route; now County Road V67 |
| Iowa 160 | 0.82 | 1.32 | Wild Cat Den State Park | US 61 | 01930-01-011930 | 01947-01-011947 | Renumbered Iowa 389 so Iowa 160 could be reused as a spur of Iowa 60 (this section now Iowa 415) |
| Iowa 160 | 2.446 | 3.936 | Iowa 415 at Ankeny | I-35 at Ankeny | 01947-01-011947 | current | extended east from US 69 to I-35 in 1980 |
| Iowa 161 | 1.15 | 1.85 | Iowa 25 in Guthrie County | Springbrook State Park | 01938-01-011938 | 01944-01-011944 | Renumbered Iowa 384 so Iowa 161 could be reused as a spur of US 61 |
| Iowa 161 | 0.47 | 0.76 | US 61 in Keokuk | Illinois state line | 01944-01-011944 | 01951-01-011951 | Replaced by US 136 |
| Iowa 161 | 1.224 | 1.970 | Iowa 141 at Dedham | Iowa 141 near Dedham | 01951-01-011951 | 02003-01-012003 | Former route of Iowa 141; now County Roads E60 and N33 |
| Iowa 162 | 2.660 | 4.281 | Pammel State Park | Iowa 92 in Madison County | 01930-01-011930 | 01982-01-011982 | 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 | 02000-01-012000 | 02006-01-012006 | Former section of US 218; became part of relocated US 18 |
| Iowa 163 | 1 | 1.6 | Ambrose A. Call State Park | US 169 near Algona | 01930-01-011930 | 01934-01-011934 | Park access road; renumbered Iowa 274 when US 163 was designated |
| Iowa 163 | 166.270 | 267.586 | US 69 in Des Moines | US 34 at Burlington | 01937-01-011937 | current | |
| Iowa 164 | 3.79 | 6.10 | US 30 in Boone | Ledges State Park | 01930-01-011930 | 01990-01-011990 | Park access road; now County Road R27 |
| Iowa 165 | 4.67 | 7.52 | Lewis and Clark State Park | US 75 in Onawa | 01930-01-011930 | 01955-01-011955 | Park access road; replaced by an extended Iowa 175 |
| Iowa 165 | 0.410 | 0.660 | Abbott Drive at Omaha, Neb. | Abbott Drive at Omaha, Neb. | 01956-01-011956 | current | Only state highway west of the Missouri River |
| Iowa 166 | 0.57 | 0.92 | Hastings | US 34 near Hastings | 01930-01-011930 | 01980-11-011980 | Spur route; now County Road M16 |
| Iowa 167 | 3.21 | 5.17 | Doon | US 75 near Doon | 01930-01-011930 | 01980-01-011980 | Spur route; now Main Street, 3rd Avenue and County Road A44 |
| Iowa 168 | 2.70 | 4.35 | Iowa 83 near Minden | Shelby | 01930-01-011930 | 01980-01-011980 | Spur route; now County Road M16 |
| Iowa 169 | 3 | 4.8 | Elk Horn | Iowa 7 at Kimballton | 01930-01-011930 | 01930-01-011930 | Spur route; renumbered Iowa 173 when US 169 was created in Iowa |
| Iowa 170 | 1.68 | 2.70 | Everly | US 18 near Everly | 01930-01-011930 | 01974-01-011974 | Spur route, former portion of US 18; now County Road M27 |
| Iowa 171 | 1 | 1.6 | Wall Lake State Park (now Big Wall Lake Wildlife Area) | US 75 in Onawa | 01930-01-011930 | 01935-01-011935 | Park access road; now an unnumbered county road |
| Iowa 171 | 1.05 | 1.69 | Elberon | Iowa 21 near Elberon | 01935-01-011935 | 01980-01-011980 | Spur route; now Main Street and County Road E44 |
| Iowa 172 | 4.23 | 6.81 | Elgin | US 18 in Clermont | 01930-01-011930 | 01980-01-011980 | Spur route; now County Road W51 and Main, Clermont and Center Streets |
| Iowa 173 | 14.680 | 23.625 | Iowa 83 near Atlantic | Iowa 44 at Kimballton | 01930-01-011930 | current | Originally a spur route south to Elk Horn; extended in 1980 |
| Iowa 174 | 3.61 | 5.81 | Farragut | Iowa 2 near Farragut | 01930-01-011930 | 01976-01-011976 | Spur route; now County Road M16 |
| Iowa 175 | 221.367 | 356.256 | N-51 at Decatur, Neb | US 63 near Hudson | 01930-01-011930 | current | Originally a spur route |
| Iowa 176 | 1.21 | 1.95 | Iowa 92 near Cumberland | Cumberland | 01930-01-011930 | 01972-01-011972 | Spur route; now County Road N28 and Jackson, 1st, and Main Streets |
| Iowa 177 | 1 | 1.6 | Carson | US 59 near Carson | 01930-01-011930 | 01937-01-011937 | Spur route; decommissioned when Iowa 100 (now Iowa 92) extended west through Carson |
| Iowa 177 | 3.20 | 5.15 | Iowa 9 near Osage | Mitchell | 01937-01-011937 | 01980-01-011980 | Spur route; now County Road T28 |
| Iowa 178 | 0.98 | 1.58 | Iowa 9 near Little Rock | Little Rock | 01930-01-011930 | 01980-01-011980 | Spur route; now Main Street and Maple Avenue |
| Iowa 179 | 0.82 | 1.32 | US 69 near Klemme | Klemme | 01930-01-011930 | 01980-01-011980 | Spur route; now 168th Street and Main Street |
| Iowa 180 | 2.46 | 3.96 | Hayesville | Iowa 149 near Hayesville | 01930-01-011930 | 01980-01-011980 | Spur route; now County Road G49 |
| Iowa 181 | 3 | 4.8 | Riverside | US 161 near Riverside | 01930-01-011930 | 01931-01-011931 | Spur route; replaced by an extended Iowa 22 |
| Iowa 181 | 9.596 | 15.443 | Iowa 5 / Iowa 92 near Pleasantville | Melcher-Dallas | 01931-01-011931 | 02003-01-012003 | Spur route; now County Road S45 |
| Iowa 182 | 11.44 | 18.41 | Iowa 9 in Lansing | MN 26 at New Albin | 01930-01-011930 | 01968-12-311968 | Swapped with Iowa 26 |
| Iowa 182 | 9.051 | 14.566 | US 18 in Inwood | Iowa 9 near Larchwood | 01969-01-011969 | current | Formerly Iowa 26 |
| Iowa 183 | 29.952 | 48.203 | Iowa 127 near Mondamin | Iowa 141 in Ute | 01930-01-011930 | current | Continued south to US 6 until 1981, and to Council Bluffs city limits until 2003 |
| Iowa 184 | 26 | 42 | Blockton | US 34 near Creston | 01930-01-011930 | 01932-01-011932 | Spur route; replaced by an extended Iowa 25 |
| Iowa 184 | 15.026 | 24.182 | US 275 near Randolph | US 59 near Randolph | 01934-01-011934 | 02003-01-012003 | Originally a spur route from US 275 to Randolph; now County Road J18 |
| Iowa 185 | 1.51 | 2.43 | Iowa 14 near Conrad | Conrad | 01934-01-011934 | 01978-01-011978 | Spur route; now County Road D67 |
| Iowa 186 | 3.27 | 5.26 | US 34 near Prescott | Prescott | 01930-01-011930 | 01980-01-011980 | Spur route; now County Road N61 and 6th Avenue |
| Iowa 186 | 3.375 | 5.432 | Green Valley State Park | Iowa 25 in Creston | 01980-01-011980 | 02001-01-012001 | Park access road; now unnumbered county roads (Green Valley Road and 130th Street) and Lincoln Street |
| Iowa 187 | 9 | 14 | Iowa 10 in Alton | Hospers | 01930-01-011930 | 01931-01-011931 | Spur route; replaced by Iowa 33 |
| Iowa 187 | 28.385 | 45.681 | US 20 near Masonville | Iowa 150 near Fayette | 01931-01-011931 | current | Originally was a park access road to Backbone State Park; moved to current route in 1980 |
| Iowa 188 | 26 | 42 | US 52 / Iowa 10 at Luxemburg | US 161 at Cascade | 01930-01-011930 | 01938-01-011938 | Replaced by an extended Iowa 136 |
| Iowa 188 | 13 | 21 | US 71 at Auburn | Iowa 17 near Lake City | 01938-01-011938 | 01940-01-011940 | Formerly No. 35 and Iowa 151; replaced by an extended Iowa 175 |
| Iowa 188 | 24.231 | 38.996 | Iowa 3 near Clarksville | US 63 near Tripoli | 01945-01-011945 | current | |
| Iowa 189 | 1.00 | 1.61 | Bridgewater | Iowa 92 north or Bridgwater | 01930-01-011930 | 01980-01-011980 | Spur route; now County Road N51 |
| Iowa 190 | 10 | 16 | Ashton | Iowa 9 in Sibley | 01930-01-011930 | 01931-01-011931 | Spur route; replaced by Iowa 33 |
| Iowa 190 | 7.46 | 12.01 | Fairbank | Iowa 150 near Oelwein | 01931-01-011931 | 01980-01-011980 | Replaced by Iowa 281 |
| Iowa 191 | 22.790 | 36.677 | I-680 near Neola | Iowa 37 at Earling | 01930-01-011930 | current | continued south to US 6 until 1981, and to Council Bluffs city limits until 2003 |
| Iowa 192 | 10 | 16 | US 75 in Sloan | Iowa 141 near Hornick | 01930-01-011930 | 01931-01-011931 | Became part of an extended Iowa 140 |
| Iowa 192 | 5.090 | 8.192 | I-29 / I-80 at Council Bluffs | I-29 at Council Bluffs | 01931-01-011931 | 02017-01-012017 | Renumbered from Iowa 241; was decommissioned in 1975, but restored in 1980; truncated in 2016; now city streets |
| Iowa 193 | 10.852 | 17.465 | US 18 in Fayette County | Iowa 24 in Jackson Junction | 01930-01-011930 | 02003-01-012003 | Now County Road V68 |
| Iowa 194 | 0.86 | 1.38 | Iowa 2 in Clarinda | Clarinda Treatment Center | 01930-01-011930 | 01958-01-011958 | Hospital access road; now 16th Street |
| Iowa 195 | 3 | 4.8 | US 69 in Jewell | Ellsworth | 01930-01-011930 | 01935-01-011935 | Spur route; became part of an extended Iowa 175 |
| Iowa 195 | 2.896 | 4.661 | Iowa 4 near Plover | Plover | 01935-01-011935 | 02003-01-012003 | Spur route; now County Road C15 |
| Iowa 196 | 1 | 1.6 | US 20 near Williams | Williams | 01930-01-011930 | 01932-01-011932 | 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 |
| Iowa 196 | 10.136 | 16.312 | US 71 / Iowa 175 near Lake View | US 20 near Sac City | 01935-01-011935 | 02015-01-012015 | Replaced by a rerouted US 71 |
| Iowa 197 | 7 | 11 | Stratford | Iowa 60 near Stanhope | 01930-01-011930 | 01937-01-011937 | Spur route; became part of an extended Iowa 175 |
| Iowa 197 | 2.567 | 4.131 | Iowa 3 near Albert City | Albert City | 01937-01-011937 | 02003-01-012003 | Spur route; now Main Street and County Road N14 |
| Iowa 198 | 2.231 | 3.590 | Garrison | US 218 near Garrison | 01930-01-011930 | 02003-01-012003 | Spur route, section in Garrison removed 1980; now County Road V66 |
| Iowa 199 | 2.666 | 4.291 | Van Horne | US 218 near Van Horne | 01930-01-011930 | 02003-01-012003 | Spur route, section in Van Horne removed 1980; now County Road E44 |
| Iowa 200 | 2.163 | 3.481 | US 30 near Keystone | Keystone | 01930-01-011930 | 02003-01-012003 | Spur route, section in Keystone removed 1980; now County Road V42 |
| Iowa 201 | 4.755 | 7.652 | Norway | US 30 / US 218 near Atkins | 01930-01-011930 | 02003-01-012003 | Spur route; now County Road W24 |
| Iowa 202 | 8.13 | 13.08 | US 218 | Shellsburg | 01930-01-011930 | 01967-01-011967 | Spur route; became a county road (now numbered E36) |
| Iowa 202 | 10.461 | 16.835 | Route 202 at Coatsville, Mo | Iowa 2 near Moulton | 01969-01-011969 | current | Formerly Iowa 142 |
| Iowa 203 | 8.78 | 14.13 | Terril | Iowa 9 | 01930-01-011930 | 01980-01-011980 | Spur route; original east-west spur now County Road A34, north-south spur now County Road N14, Main and State streets |
| Iowa 204 | 5.407 | 8.702 | Iowa 2 near Garden Grove | Garden Grove | 01930-01-011930 | 02003-01-012003 | Spur route; now County Roads R20 and J69 |
| Iowa 205 | 2.927 | 4.711 | US 65 near Milo | Milo | 01930-01-011930 | 02003-01-012003 | Spur route; now County Road G58 |
| Iowa 206 | 6.221 | 10.012 | US 65 near Liberty Center | Liberty Center | 01930-01-011930 | 02003-01-012003 | Spur route; now County Road G76 |
| Iowa 207 | 3.058 | 4.921 | I-35 near New Virginia | New Virginia | 01930-01-011930 | 02003-01-012003 | Spur route; now County Road G76 |
| Iowa 208 | 14 | 23 | US 20 | Backbone State Park | 01930-01-011930 | 01931-01-011931 | Park access road; renumbered Iowa 187 |
| Iowa 208 | 11.83 | 19.04 | Iowa 2 | Blanchard | 01931-01-011931 | 01974-01-011974 | Spur route; now County Road M48 |
| Iowa 209 | 0.66 | 1.06 | Iowa 149 near Conroy | Conroy | 01931-01-011931 | 01976-01-011976 | Spur route; now County Road F34 |
| Iowa 210 | 34.781 | 55.975 | Iowa 141 near Woodward | US 65 near Collins | 01931-01-011931 | current | Originally a double spur route from Slater to Maxwell; extended in 1980 |
| Iowa 211 | 1.63 | 2.62 | Cambridge | Iowa 210 near Cambridge | 01931-01-011931 | 01980-01-011980 | Spur route; now County Road R70 |
| Iowa 212 | 20 | 32 | Iowa 8 in Dysart | US 30 in Belle Plaine | 01931-01-011931 | 01933-01-011933 | Replaced by an extended Iowa 73, which was renumbered Iowa 212 9 months later; this portion became part of Iowa 21 a month later |
| Iowa 212 | 12.157 | 19.565 | Iowa 21 near Belle Plaine | US 6 at Marengo | 01934-01-011934 | current | continued northwest to US 30 from 1937 to 1980 |
| Iowa 213 | 3.72 | 5.99 | Blakesburg | US 34 north of Blakesburg | 01931-01-011931 | 01980-12-011980 | Spur route; now County Road T61 |
| Iowa 214 | 5.736 | 9.231 | Iowa 175 near Ivester | Wellsburg | 01931-01-011931 | 02003-01-012003 | Spur route; now County Road T19 |
| Iowa 215 | 8.738 | 14.062 | Union | Iowa 175 in Eldora | 01931-01-011931 | 02003-01-012003 | Spur route; now County Road S62 |
| Iowa 216 | 1.70 | 2.74 | Iowa 5 | Exline | 01931-01-011931 | 01981-01-011981 | Spur route; now County Road T16 |
| Iowa 217 | 4.96 | 7.98 | Breda | US 71 | 01931-01-011931 | 01989-01-011989 | Spur route; now County Road E16 |
| Iowa 219 | 1.53 | 2.46 | Iowa 9 near Lake Park | Lake Park | 01931-01-011931 | 01980-12-011980 | Spur route; now County Road M27 |
| Iowa 220 | 7.233 | 11.640 | US 6 at South Amana | US 151 at Amana | 01931-01-011931 | current | Continued east to East Amana and south to Upper South Amana until 1980 |
| Iowa 221 | 11 | 18 | US 71 near Albert City | Albert City | 01931-01-011931 | 01937-01-011937 | Spur route; became a county road (now numbered C29) |
| Iowa 221 | 42.61 | 68.57 | Iowa 5 near Cherokee | Iowa 17 / Iowa 10 at Pocahontas | 01937-01-011937 | 01945-01-011945 | Extended in both directions and renumbered Iowa 3 |
| Iowa 221 | 3.909 | 6.291 | I-35 near Story City | Roland | 01947-01-011947 | 02003-01-012003 | Spur route, section from I-35 to US 69 removed 1980; now County Road E18 |
| Iowa 222 | 15.12 | 24.33 | Iowa 15 near Ottosen | Livermore | 01931-01-011931 | 01980-01-011980 | Spur route; now County Road C20 |
| Iowa 223 | 12.22 | 19.67 | Iowa 330 near Baxter | Iowa 14 near Baxter | 01931-01-011931 | 01997-01-011997 | Originally a spur route, extended west from Baxter in 1980; now County Road F17 |
| Iowa 224 | 10.587 | 17.038 | US 6 near Kellogg | Iowa 14 near Laurel | 01931-01-011931 | current | Originally a spur route; extended north from Kellogg in 1980 |
| Iowa 225 | 7.688 | 12.373 | Sully | Iowa 146 in Searsboro | 01931-01-011931 | 02003-01-012003 | Spur route; now County Road F62 |
| Iowa 226 | 10.78 | 17.35 | US 18 | Titonka | 01931-01-011931 | 01980-12-011980 | Spur route; now County Road P64 |
| Iowa 227 | 5.39 | 8.67 | US 218 near Stacyville | Stacyville | 01931-01-011931 | 01991-01-011991 | Spur route; now County Road T40 |
| Iowa 228 | 0.85 | 1.37 | US 6 (this section became County Road F58 in 2003) near Walcott | Walcott | 01931-01-011931 | 01964-01-011964 | Spur route; now Main Street |
| Iowa 229 | 5.233 | 8.422 | Garwin | US 63 in Tama County | 01931-01-011931 | 02003-01-012003 | Spur route; now County Road E29 |
| Iowa 230 | 1 | 1.6 | Sergeant Bluff | US 75 near Sergeant Bluff | 01931-01-011931 | 01934-01-011934 | 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 |
| Iowa 230 | 8.60 | 13.84 | US 75 near Sergeant Bluff | US 75 in Sioux City | 01934-01-011934 | 01965-01-011965 | Spur route; now Transit Avenue, Morningside Avenue, Lakeport Road and a county road (now numbered K29) |
| Iowa 231 | 1.83 | 2.95 | Iowa 10 near Ireton | Ireton | 01931-01-011931 | 01981-01-011981 | 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 | 02000-01-012000 | 02003-01-012003 | Former section of US 34, unsigned; now Main Street |
| Iowa 232 | 1.99 | 3.20 | Earlham | I-80 near Earlham | 01931-01-011931 | 01980-01-011980 | Spur route; now County Road P57 |
| Iowa 233 | 5.30 | 8.53 | Albion | Iowa 14 near Rhodes | 01931-01-011931 | 01989-01-011989 | Spur route; became part of relocated Iowa 330 |
| Iowa 234 | 6.72 | 10.81 | US 30 in State Center | Iowa 330 near Rhodes | 01931-01-011931 | 01994-01-011994 | Originally a spur route; only the section north of CR E63 remained after 1989; now an unnumbered county road |
| Iowa 235 | 3 | 4.8 | Iowa 234 near Rhodes | Rhodes | 01931-01-011931 | 01935-01-011935 | Spur route; became an unnumbered county road (now 285th Street) |
| Iowa 235 | 1.24 | 2.00 | Rhodes | Iowa 234 near Rhodes | 01935-01-011935 | 01966-01-011966 | Spur route; renumbered Iowa 245 when I-235 was designated |
| Iowa 236 | 1.18 | 1.90 | Templeton | US 71 / Iowa 141 near Templeton | 01931-01-011931 | 01987-01-011987 | Spur route; now local roads (Main and 2nd Streets) and County Road N18 |
| Iowa 237 | 1.41 | 2.27 | Iowa 9 near Ocheyedan | Ocheyedan | 01931-01-011931 | 01981-01-011981 | Spur route; section in Ocheyedan removed in 1980; now County Road L58 |
| Iowa 238 | 1.063 | 1.711 | Iowa 9 near Harris | Harris | 01931-01-011931 | 02003-01-012003 | Spur route; was decommissioned in 1981, but was restored in 1987; now County Road M20 |
| Iowa 239 | 0.510 | 0.821 | Waubonsie State Park | Iowa 2 in Fremont County | 01931-01-011931 | 02003-01-012003 | Park access road; now County Road L48 |
| Iowa 240 | 6.389 | 10.282 | Royal | US 71 in Clay County | 01931-01-011931 | 02003-01-012003 | Spur route; now Main Street, County Roads M36 and B40 |
| Iowa 241 | 5 | 8.0 | US 34 / US 275 at Council Bluffs | US 34 / US 275 | 01931-01-011931 | 01931-01-011931 | Renumbered Iowa 192 |
| Iowa 241 | 0.99 | 1.59 | Readlyn | Iowa 3 near Readlyn | 01931-01-011931 | 01980-01-011980 | Spur route; now local roads |
| Iowa 242 | 5.855 | 9.423 | US 34 in Mills County | Silver City | 01931-01-011931 | 02003-01-012003 | Spur route; now County Road L55 |
| Iowa 243 | 7.97 | 12.83 | Iowa 140 near Kingsley | Pierson | 01931-01-011931 | 01980-01-011980 | Spur route; now County Road D12 |
| Iowa 243 | 0.559 | 0.900 | Black Hawk Lake State Park | US 71 / Iowa 175 near Wall Lake | 01980-01-011980 | 02003-01-012003 | Park access road; now an unnumbered county road |
| Iowa 244 | 1.96 | 3.15 | Henderson | US 59 | 01931-01-011931 | 01980-01-011980 | Spur route; now County Roads H12 and M21 and Maple Street |
| Iowa 244 | 0.771 | 1.241 | I-80 near Neola | Iowa 191 in Neola | 01980-01-011980 | 02003-01-012003 | Now County Road L55 |
| Iowa 245 | 1.54 | 2.48 | Iowa 9 near Estherville | Fort Defiance State Park | 01931-01-011931 | 01961-01-011961 | Park access road; became a county road (now numbered N26) |
| Iowa 245 | 1.24 | 2.00 | Rhodes | Iowa 234 near Rhodes | 01966-01-011966 | 01990-01-011990 | Spur route; portion outside of Rhodes removed in 1989; now County Road E63 |
| Iowa 246 | 3.26 | 5.25 | US 61 in Zwingle | La Motte | 01931-01-011931 | 01981-01-011981 | Spur route; section outside La Motte deleted in 1980; now County Road D55 and city streets |
| Iowa 247 | 0.68 | 1.09 | Chelsea | Iowa 212 near Chelsea | 01931-01-011931 | 01963-01-011963 | Spur route; became a county road (now numbered V18) |
| Iowa 248 | 0.54 | 0.87 | Independence State Hospital | US 20 in Independence | 01931-01-011931 | 01980-01-011980 | Hospital access road; now 20th Avenue SW |
| Iowa 249 | 0.665 | 1.070 | Iowa 78 near Winfield | Winfield | 01931-01-011931 | 02003-01-012003 | Spur route; now County Road V66 |
| Iowa 250 | 0.59 | 0.95 | Lakota | US 169 / Iowa 9 near Lakota | 01932-01-011932 | 01980-01-011980 | Spur route; now a local road |
| Iowa 251 | 1.71 | 2.75 | St. Charles | I-35 near St. Charles | 01932-01-011932 | 01980-01-011980 | Spur route; now County Road G50 |
| Iowa 252 | 0.584 | 0.940 | US 61 / Iowa 92 near Grandview | Grandview | 01932-01-011932 | 02003-01-012003 | Spur route |
| Iowa 253 | 0.932 | 1.500 | Iowa 14 near Williamson | Williamson | 01932-01-011932 | 02003-01-012003 | Spur route |
| Iowa 254 | 0.45 | 0.72 | Iowa 92 at Massena | Massena | 01932-01-011932 | 01968-12-311968 | Spur route; renumbered Iowa 322 |
| Iowa 254 | 7.91 | 12.73 | Iowa 9 near Buffalo Center | MN 254 near Rake | 01969-01-011969 | 01980-01-011980 | Spur route; formerly Iowa 322 |
| Iowa 254 | 2.7 | 4.3 | dead end northwest of Nashua | dead end southeast of Nashua | 02003-01-012003 | 02004-01-012004 | Former section of US 218 |
| Iowa 255 | 2.26 | 3.64 | Orchard | US 218 near Orchard | 01932-01-011932 | 01980-01-011980 | Spur route |
| Iowa 256 | 0.80 | 1.29 | Iowa 17 near Corwith | Corwith | 01932-01-011932 | 01980-01-011980 | Spur route |
| Iowa 257 | 0.58 | 0.93 | US 18 near Dickens | Dickens | 01933-01-011933 | 01960-01-011960 | Spur route |
| Iowa 258 | 1.989 | 3.201 | I-35 near Van Wert | US 69 near Van Wert | 01933-01-011933 | 02003-01-012003 | Originally a spur route |
| Iowa 259 | 1.001 | 1.611 | US 169 near Tingley | Tingley | 01933-01-011933 | 02003-01-012003 | Spur route; section in Tingley removed 1980 |
| Iowa 260 | 2.12 | 3.41 | Shannon City | US 169 near Shannon City | 01933-01-011933 | 01977-01-011977 | Spur route |
| Iowa 261 | 33.02 | 53.14 | Iowa 1 in Iowa City | US 151 | 01930-01-011930 | 01962-01-011962 | Numbered as a branch of US 161; replaced by relocated Iowa 1 |
| Iowa 262 | 1.99 | 3.20 | US 69 near Galt | Galt | 01933-01-011933 | 01980-01-011980 | Spur route |
| Iowa 263 | 2.14 | 3.44 | Coulter | Latimer | 01933-01-011933 | 01980-01-011980 | Double spur route with Iowa 3 |
| Iowa 263 | 12.511 | 20.135 | Iowa 14 in Grundy County | US 20 near Cedar Falls | 02000-01-012000 | 02003-01-012003 | Former section of US 20 |
| Iowa 264 | 2.39 | 3.85 | Linn Grove | Iowa 10 near Linn Grove | 01933-01-011933 | 01980-01-011980 | Spur route |
| Iowa 265 | 2.08 | 3.35 | Kent | US 34 near Kent | 01934-01-011934 | 01961-01-011961 | Spur route |
| Iowa 266 | 1.709 | 2.750 | US 69 near Weldon | Weldon | 01934-01-011934 | 02003-01-012003 | Spur route; section in Weldon removed 1980 |
| Iowa 267 | 1.19 | 1.92 | Iowa 93 near Randalia | Randalia | 01934-01-011934 | 01980-01-011980 | Spur route |
| Iowa 268 | 6.29 | 10.12 | US 59 near Irwin | Irwin | 01934-01-011934 | 01971-01-011971 | Spur route; became part of an extended Iowa 37 |
| Iowa 269 | 3.01 | 4.84 | Iowa 16 near Stockport | Stockport | 01934-01-011934 | 01980-01-011980 | Spur route |
| Iowa 270 | 1.80 | 2.90 | Iowa 16 near Hillsboro | Hillsboro | 01934-01-011934 | 01980-01-011980 | Spur route |
| Iowa 271 | 7 | 11 | Marne | US 71 in Atlantic | 01934-01-011934 | 01935-01-011935 | Spur route; replaced by an extended Iowa 83 |
| Iowa 271 | 0.84 | 1.35 | Iowa 4 near Yale | Yale | 01935-01-011935 | 01980-01-011980 | Spur route |
| Iowa 272 | 6.45 | 10.38 | Elma | US 63 near Elma | 01934-01-011934 | 01992-01-011992 | Spur route; formerly Iowa 52 |
| Iowa 273 | 10.025 | 16.134 | Lake Wapello State Park | US 63 near Drakesville | 01935-01-011935 | 02003-01-012003 | Park access road |
| Iowa 274 | 1.99 | 3.20 | Ambrose A. Call State Park | US 169 near Algona | 01934-01-011934 | 01986-01-011986 | Park access road; formerly Iowa 163 |
| Iowa 276 | 4.711 | 7.582 | Spirit Lake city limits | Minnesota state line | 01934-01-011934 | 02003-01-012003 | Park access road |
| Iowa 277 | 6.24 | 10.04 | Numa | Iowa 5 near Centerville | 01935-01-011935 | 01980-01-011980 | Spur route |
| Iowa 278 | 2.05 | 3.30 | Rathbun | Iowa 5 near Rathbun | 01935-01-011935 | 01980-01-011980 | Spur route |
| Iowa 279 | 1.983 | 3.191 | US 30 / US 218 near Atkins | Atkins | 01935-01-011935 | 02003-01-012003 | Spur route; section in Atkins removed 1980 |
| Iowa 280 | 2.62 | 4.22 | US 30 / US 218 near Newhall | Newhall | 01935-01-011935 | 01965-01-011965 | Spur route; renumbered Iowa 287 when I-280 was designated |
| Iowa 281 | 28.166 | 45.329 | Waterloo city limits | Iowa 150 at Oelwein | 01935-01-011935 | current | Originally a spur route east to Dunkerton; extended in 1980 |
| Iowa 282 | 5.283 | 8.502 | Quasqueton | Iowa 939 near Winthrop | 01935-01-011935 | 02003-01-012003 | Spur route |
| Iowa 283 | 5.861 | 9.432 | Brandon | Iowa 150 near Brandon | 01935-01-011935 | 02003-01-012003 | Spur route |
| Iowa 284 | 5.58 | 8.98 | Aurora | Iowa 187 at Lamont | 01935-01-011935 | 01980-01-011980 | Spur route |
| Iowa 285 | 0.796 | 1.281 | US 30 in Arcadia | Arcadia | 01935-01-011935 | 02003-01-012003 | Spur route |
| Iowa 286 | 9.932 | 15.984 | US 30 in Glidden | Lanesboro | 01935-01-011935 | 02003-01-012003 | Spur route |
| Iowa 287 | 7.52 | 12.10 | Farnhamville | Iowa 47 in Farnhamville | 01935-01-011935 | 01940-01-011940 | Spur route; replaced by an extended Iowa 175 |
| Iowa 287 | 6.19 | 9.96 | Bradgate | Iowa 3 in Gilmore City | 01942-01-011942 | 01965-01-011965 | Spur route |
| Iowa 287 | 1.833 | 2.950 | US 30 / US 218 near Newhall | Newhall | 01965-01-011965 | 02003-01-012003 | Spur route; section in Newhall removed 1980 |
| Iowa 288 | 4.58 | 7.37 | US 65 near Manly | Plymouth | 01935-01-011935 | 01980-01-011980 | Spur route |
| Iowa 289 | 6.14 | 9.88 | Alta Vista | US 63 near Lourdes | 01935-01-011935 | 01980-01-011980 | Spur route |
| Iowa 289 | 2.252 | 3.624 | US 61 near Fort Madison | US 61 near Fort Madison | 02000-01-012000 | 02003-01-012003 | Former section of US 61 southwest of Fort Madison; had two sections |
| Iowa 290 | 1.99 | 3.20 | Farmersburg | Iowa 13 near Farmersburg | 01935-01-011935 | 01980-01-011980 | Spur route |
| Iowa 291 | 1.01 | 1.63 | Low Moor | US 30 near Low Moor | 01935-01-011935 | 01979-01-011979 | Spur route |
| Iowa 292 | 3.17 | 5.10 | Linden | Iowa 44 | 01935-01-011935 | 01980-01-011980 | Spur route |
| Iowa 293 | 1.42 | 2.29 | Iowa 90 near Van Meter | Van Meter | 01935-01-011935 | 01980-01-011980 | Spur route |
| Iowa 294 | 6.147 | 9.893 | Iowa 2 in Decatur County | Grand River | 01935-01-011935 | 02003-01-012003 | Spur route |
| Iowa 295 | 5.09 | 8.19 | Westgate | Iowa 150 near Maynard | 01935-01-011935 | 01980-01-011980 | Spur route |
| Iowa 296 | 4.44 | 7.15 | CR C24 near Wadena | Iowa 56 near Wadena | 01935-01-011935 | 01980-01-011980 | Spur route |
| Iowa 296 | 0.275 | 0.443 | — | — | 02000-01-012000 | 02011-01-012011 | Former section of Iowa 28 |
| Iowa 297 | 4.25 | 6.84 | Alexander | Iowa 10 | 01935-01-011935 | 01939-01-011939 | Spur route; replaced by an extended Iowa 107 |
| Iowa 297 | 3.543 | 5.702 | Gilbertville | Raymond | 01940-01-011940 | 02003-01-012003 | Double spur with I-380 |
| Iowa 298 | 4.22 | 6.79 | Iowa 60 near Kamrar | Kamrar | 01935-01-011935 | 01966-01-011966 | Spur route; until 1958 went from US 69 to Kamrar |
| Iowa 299 | 5.556 | 8.942 | New Providence | Iowa 175 near Eldora | 01935-01-011935 | 02003-01-012003 | Spur route |
| Iowa 300 | 1.411 | 2.271 | Modale | I-29 near Modale | 01935-01-011935 | 02003-01-012003 | Spur route |
| Iowa 301 | 2.045 | 3.291 | I-29 near Little Sioux | Little Sioux | 01935-01-011935 | 02003-01-012003 | Spur route |
| Iowa 302 | 3.00 | 4.83 | Thor | Iowa 3 near Thor | 01935-01-011935 | 01980-01-011980 | Spur route |
| Iowa 303 | 3.51 | 5.65 | US 34 near Fairfield | Libertyville | 01935-01-011935 | 01981-01-011981 | Spur route |
| Iowa 304 | 1.59 | 2.56 | Iowa 78 near Ollie | Ollie | 01935-01-011935 | 01980-01-011980 | Spur route |
| Iowa 305 | 2.554 | 4.110 | Letts | US 61 / Iowa 92 near Letts | 01935-01-011935 | 02003-01-012003 | Spur route |
| Iowa 306 | 0.783 | 1.260 | US 65 near Derby | Derby | 01935-01-011935 | 02003-01-012003 | Spur route |
| Iowa 307 | 5.31 | 8.55 | US 169 near East Peru | East Peru | 01935-01-011935 | 01975-01-011975 | Spur route; decommissioned when US 169 was rerouted south of Winterset |
| Iowa 308 | 7.32 | 11.78 | US 63 near New Sharon | Barnes City | 01935-01-011935 | 01966-01-011966 | Spur route |
| Iowa 309 | 2.32 | 3.73 | Beacon | Iowa 137 in Oskaloosa | 01935-01-011935 | 01980-01-011980 | Spur route |
| Iowa 310 | 1.68 | 2.70 | Iowa 92 near Harvey | Harvey | 01935-01-011935 | 01966-01-011966 | Spur route |
| Iowa 311 | 4.73 | 7.61 | Liscomb | Iowa 14 near Liscomb | 01935-01-011935 | 01989-01-011989 | Spur route; section in Liscomb removed 1980 |
| Iowa 312 | 6.19 | 9.96 | Iowa 9 near Riceville | McIntire | 01935-01-011935 | 01980-01-011980 | Spur route |
| Iowa 312 | 0.883 | 1.421 | — | — | 02002-01-012002 | 02003-01-012003 | Former section of US 65; had two sections |
| Iowa 313 | 1.591 | 2.560 | US 59 near Melvin | Melvin | 01935-01-011935 | 02002-01-012002 | Spur route; section in Melvin removed 1980 |
| Iowa 314 | 6.277 | 10.102 | Ayrshire | US 18 near Ruthven | 01935-01-011935 | 02003-01-012003 | Spur route |
| Iowa 315 | 4.158 | 6.692 | Iowa 4 near Palmer | Palmer | 01935-01-011935 | 02003-01-012003 | Spur route |
| Iowa 316 | 5.183 | 8.341 | Iowa 5 near Swan | Runnells city limits | 01935-01-011935 | current | Spur route; continued south to Iowa 163 from 1981 to 2003 |
| Iowa 317 | 0.71 | 1.14 | US 65 near Zearing | Zearing | 01935-01-011935 | 01980-01-011980 | Spur route; continued west to McCallsburg until 1954 |
| Iowa 318 | 5.51 | 8.87 | Clutier | Iowa 21 near Clutier | 01935-01-011935 | 01980-01-011980 | Spur route |
| Iowa 319 | 0.50 | 0.80 | Gravity | Iowa 148 at Gravity | 01935-01-011935 | 01980-01-011980 | Spur route; continued east to Conway until 1961 |
| Iowa 320 | 4.25 | 6.84 | US 169 near Badger | Badger | 01935-01-011935 | 01963-01-011963 | Spur route |
| Iowa 321 | 6.03 | 9.70 | Clare | Iowa 5 near Clare | 01935-01-011935 | 01963-01-011963 | Spur route |
| Iowa 322 | 7.91 | 12.73 | Iowa 9 near Buffalo Center | MN 254 near Rake | 01935-01-011935 | 01968-12-311968 | Spur route; renumbered Iowa 254 |
| Iowa 322 | 0.45 | 0.72 | Iowa 92 at Massena | Massena | 01969-01-011969 | 01972-01-011972 | Spur route; formerly Iowa 254 |
| Iowa 322 | 2.660 | 4.281 | Pammel State Park | Iowa 92 in Madison County | 01982-01-011982 | 02003-01-012003 | Park access road; formerly Iowa 162 |
| Iowa 323 | 3.74 | 6.02 | Iowa 17 near Woolstock | Woolstock | 01935-01-011935 | 01980-01-011980 | Spur route |
| Iowa 324 | 0.79 | 1.27 | Lawton | US 20 near Lawton | 01935-01-011935 | 01954-01-011954 | Spur route; decommissioned when US 20 was rerouted closer to Lawton |
| Iowa 324 | 0.510 | 0.821 | Iowa 175 near Onawa | Lewis and Clark State Park | 01956-01-011956 | 02003-01-012003 | Park access road |
| Iowa 325 | 3.617 | 5.821 | Spillville | US 52 near Calmar | 01935-01-011935 | 02003-01-012003 | Spur route; section in Spillville removed 1980 |
| Iowa 326 | 2.18 | 3.51 | Bristow | Iowa 3 near Bristow | 01935-01-011935 | 01981-01-011981 | Spur route |
| Iowa 327 | 2.070 | 3.331 | Iowa 276 in Spirit Lake | near Orleans | 01935-01-011935 | 02003-01-012003 | Spur route |
| Iowa 328 | 2.29 | 3.69 | US 20 near Galva | Galva | 01935-01-011935 | 01980-12-011980 | Spur route |
| Iowa 329 | 4.85 | 7.81 | US 169 at Boxholm | Pilot Mound | 01935-01-011935 | 01980-01-011980 | Spur route |
| Iowa 330 | 2.31 | 3.72 | Ionia | US 18 near Ionia | 01935-01-011935 | 01948-01-011948 | Spur route; renumbered Iowa 393 so Iowa 330 could be reused as a spur of US 30 |
| Iowa 330 | 47.748 | 76.843 | I-80 / US 6 / US 65 at Altoona | Iowa 14 near Albion | 01948-01-011948 | current | Originally went from US 30 to Marshalltown; extended west in 1969 and was relocated to bypass Marshalltown in 1989 |
| Iowa 331 | 1.83 | 2.95 | Eldridge | US 61 near Eldridge | 01935-01-011935 | 01967-01-011967 | Spur route |
| Iowa 331 | 3.801 | 6.117 | Dead end near I-35 in Des Moines | Iowa 28 in Des Moines | 02002-01-012002 | 02005-01-012005 | Former section of Iowa 5 |
| Iowa 332 | 1.00 | 1.61 | Pilot Knob State Park | Iowa 9 near Forest City | 01935-01-011935 | 01980-01-011980 | Park access road |
| Iowa 333 | 1.558 | 2.507 | I-29 at Hamburg | US 275 in Hamburg | 01935-01-011935 | 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 |
| Iowa 334 | 1.87 | 3.01 | US 63 near Frederika | Frederika | 01935-01-011935 | 01980-01-011980 | Spur route |
| Iowa 334 | 6.600 | 10.622 | — | — | 02006-01-012006 | 02007-01-012007 | Former section of US 34 |
| Iowa 335 | 0.64 | 1.03 | Iowa 141 near Dawson | Dawson | 01935-01-011935 | 01980-01-011980 | Spur route |
| Iowa 335 | 1.536 | 2.472 | Iowa 163 in Otley | Iowa 163 in Otley | 01999-01-011999 | 02001-01-012001 | Former section of Iowa 163 |
| Iowa 336 | 2.48 | 3.99 | Iowa 150 near Rowley | Rowley | 01936-01-011936 | 01980-01-011980 | Spur route |
| Iowa 337 | 3.36 | 5.41 | Iowa 9 near Grafton | Grafton | 01936-01-011936 | 01980-01-011980 | Spur route |
| Iowa 337 | 2.764 | 4.448 | US 218 in Charles City | US 18 in Charles City | 02000-01-012000 | 02001-01-012001 | Former section of US 218 |
| Iowa 337 | 1.085 | 1.746 | US 151 in Langworthy | US 151 in Langworthy | 02003-01-012003 | 02004-01-012004 | Former section of US 151 |
| Iowa 338 | 1.02 | 1.64 | Bondurant | US 65 | 01936-01-011936 | 01972-01-011972 | Spur route |
| Iowa 339 | 6.15 | 9.90 | George | Iowa 9 near George | 01936-01-011936 | 02000-01-012000 | Spur route |
| Iowa 340 | 2.231 | 3.590 | Pikes Peak State Park | Iowa 76 in McGregor | 01936-01-011936 | 02003-01-012003 | Park access road |
| Iowa 340 | 1.160 | 1.867 | Dead end in Batavia | US 34 in Batavia | 02005-01-012005 | 02007-01-012007 | Former section of US 34 |
| Iowa 341 | 2.10 | 3.38 | Lost Island Park | US 18 near Ruthven | 01936-01-011936 | 01988-01-011988 | Park access road |
| Iowa 341 | 0.062 | 0.100 | Ruthven | US 18 near Ruthven | 01993-01-011993 | 02003-01-012003 | Spur route; restoration of part of the previous Iowa 341 |
| Iowa 342 | 0.95 | 1.53 | Iowa 141 near Jamaica | Jamaica | 01936-01-011936 | 01980-01-011980 | Spur route |
| Iowa 342 | 2.2 | 3.5 | Dead end north of Eddyville | Iowa 137 in Eddyville | 02004-01-012004 | 02005-01-012005 | Former section of US 63 |
| Iowa 343 | 1.01 | 1.63 | Iowa 333 near Northboro | Northboro | 01937-01-011937 | 01980-01-011980 | Spur route |
| Iowa 344 | 7.06 | 11.36 | Iowa 2 in Bedford | Iowa 319 near Conway | 01937-01-011937 | 01943-01-011943 | Park access road; became part of an extended Iowa 49 |
| Iowa 344 | 1.075 | 1.730 | State fish hatchery | US 169 near Mount Ayr | 01943-01-011943 | 02001-01-012001 | Fish hatchery access road |
| Iowa 345 | 0.42 | 0.68 | Iowa 17 near Graettinger | Graettinger | 01937-01-011937 | 01960-01-011960 | Spur route |
| Iowa 346 | 12.470 | 20.069 | US 218 / Iowa 27 at Nashua | US 18 / US 63 near New Hampton | 01937-01-011937 | current | |
| Iowa 347 | 1.08 | 1.74 | Locust Street at Omaha, Neb. | Locust Street at Omaha, Neb. | 01937-01-011937 | 01986-01-011986 | |
| Iowa 348 | 0.88 | 1.42 | Iowa 347 | Carter Lake | 01937-01-011937 | 01967-01-011967 | |
| Iowa 349 | 1.032 | 1.661 | Lake Ahquabi State Park | US 65 / US 69 near Indianola | 01938-01-011938 | 02003-01-012003 | Park access road |
| Iowa 350 | 2.55 | 4.10 | US 6 near Davenport | Iowa 122 in Davenport | 01938-01-011938 | 01958-01-011958 | Now Hickory Grove Road |
| Iowa 351 | 0.86 | 1.38 | Rembrandt | US 71 near Rembrandt | 01938-01-011938 | 01981-01-011981 | Spur route; section in Rembrandt removed 1980 |
| Iowa 352 | 0.75 | 1.21 | Truesdale | US 71 near Truesdale | 01938-01-011938 | 01981-01-011981 | Spur route; section in Truesdale removed 1980 |
| Iowa 353 | 0.35 | 0.56 | Rowan | Iowa 3 at Rowan | 01938-01-011938 | 01980-01-011980 | Spur route |
| Iowa 354 | 0.35 | 0.56 | Mallard | Iowa 17 near Mallard | 01938-01-011938 | 01960-01-011960 | Spur route |
| Iowa 355 | 0.33 | 0.53 | Iowa 175 near Radcliffe | Radcliffe | 01938-01-011938 | 01961-01-011961 | Spur route |
| Iowa 356 | 6.37 | 10.25 | Packwood | Iowa 1 near Packwood | 01938-01-011938 | 01981-01-011981 | Spur route; section in Packwood removed 1980 |
| Iowa 356 | 0.949 | 1.527 | Milford | West Okoboji | 02000-01-012000 | 02003-01-012003 | Former section of US 71 |
| Iowa 357 | 0.59 | 0.95 | Blockton | Iowa 25 near Blockton | 01938-01-011938 | 01964-01-011964 | Spur route |
| Iowa 358 | 1.55 | 2.49 | Whittemore | US 18 / Iowa 15 near Whittemore | 01938-01-011938 | 01980-01-011980 | Spur route |
| Iowa 359 | 7.383 | 11.882 | Buckeye | Iowa 941 in Alden | 01938-01-011938 | 02003-01-012003 | Spur route |
| Iowa 360 | 0.64 | 1.03 | Iowa 5 near Newell | Newell | 01938-01-011938 | 01964-01-011964 | Spur route |
| Iowa 361 | 0.38 | 0.61 | Bayard | Iowa 25 near Bayard | 01938-01-011938 | 01962-01-011962 | Spur route |
| Iowa 362 | 1.17 | 1.88 | Macedonia | US 59 near Macedonia | 01938-01-011938 | 01980-01-011980 | Spur route |
| Iowa 362 | 5.469 | 8.802 | DeSoto National Wildlife Refuge | I-29 at Loveland | 01980-01-011980 | 02003-01-012003 | Park access road |
| Iowa 363 | 1.616 | 2.601 | Iowa 150 near Urbana | I-380 / Iowa 27 in Urbana | 01939-01-011939 | 02003-01-012003 | Spur route; formerly Iowa 92; rerouted to end at I-380 in 1984 |
| Iowa 364 | 6.140 | 9.881 | Iowa 76 near Waukon Junction | Harpers Ferry | 01938-01-011938 | 02003-01-012003 | Spur route; section north of the bridge in Harpers Ferry removed 1980 |
| Iowa 365 | 1.07 | 1.72 | Tracy | Iowa 964 near Tracy | 01939-01-011939 | 01980-11-011980 | Spur route; did not extend to relocated Iowa 92 when Iowa 92 was rerouted in 1978 |
| Iowa 366 | 0.51 | 0.82 | US 75 near Blencoe | Blencoe | 01939-01-011939 | 01964-01-011964 | Spur route |
| Iowa 367 | 6 | 9.7 | Nebraska border | US 275 in Council Bluffs | 01939-01-011939 | 01941-01-011941 | Replaced by US 275 |
| Iowa 367 | 3.39 | 5.46 | Rutland | US 169 near Humboldt | 01942-01-011942 | 01980-01-011980 | Spur route |
| Iowa 368 | 0.50 | 0.80 | Renwick | Iowa 60 near Renwick | 01939-01-011939 | 01964-01-011964 | Spur route |
| Iowa 368 | 0.140 | 0.225 | 200th Avenue northwest of Hartford | Dead end | 02002-01-012002 | current | Former section of Iowa 5 |
| Iowa 369 | 2 | 3.2 | Iowa 92 near Knoxville | Coal mine | 01939-01-011939 | 01941-01-011941 | Now County Road T17 |
| Iowa 369 | 5.54 | 8.92 | Iowa 2 near Moulton | Unionville | 01942-01-011942 | 01980-01-011980 | Spur route |
| Iowa 370 | 0.46 | 0.74 | Iowa 57 | Dike | 01939-01-011939 | 01952-01-011952 | Spur route |
| Iowa 370 | 3.265 | 5.255 | N-370 at Bellevue, Neb. | I-29 / US 275 near Council Bluffs | 01953-01-011953 | 02014-01-012014 | Originally ended at US 275 (pre-2003 route); decommissioned in 1980, but restored west of I-29 in 1983 |
| Iowa 371 | 0.715 | 1.151 | Lake Keomah State Park | Iowa 92 near Keomah Village | 01939-01-011939 | 02003-01-012003 | Park access road |
| Iowa 372 | 2.60 | 4.18 | Preparation Canyon State Park | Iowa 183 near Moorhead | 01939-01-011939 | 01968-01-011968 | Park access road |
| Iowa 373 | 4.05 | 6.52 | Iowa 13 near Waterville | Waterville | 01942-01-011942 | 01964-01-011964 | Spur route |
| Iowa 373 | 2.307 | 3.713 | — | — | 02002-01-012002 | 02003-01-012003 | Former section of US 61 just southwest of Muscatine |
| Iowa 374 | 7.99 | 12.86 | US 71 near Sioux Rapids | Webb | 01942-01-011942 | 01980-01-011980 | Spur route |
| Iowa 374 | 3.6 | 5.8 | Iowa 163 in Monroe | Dead end in Monroe | 02000-01-012000 | 02000-01-012000 | Former section of Iowa 163 |
| Iowa 375 | 2.95 | 4.75 | US 6 in Council Bluffs | US 275 / Iowa 92 in Council Bluffs | 01941-01-011941 | 01971-01-011971 | Now 4th Street, 9th Avenue, 3rd Street, and Harry Langdon Boulevard |
| Iowa 376 | 0.46 | 0.74 | Iowa 3 near Colesburg | Colesburg | 01942-01-011942 | 01965-01-011965 | Spur route |
| Iowa 376 | 10.334 | 16.631 | I-129 / US 20 / US 75 at Sioux City | US 75 at Sioux City | 02001-01-012001 | current | US 75 Business in Sioux City |
| Iowa 377 | 0.55 | 0.89 | Harbor Drive in Sioux City | Iowa 970 in Sergeant Bluff | 01942-01-011942 | 01980-01-011980 | Airport access road |
| Iowa 378 | 2.13 | 3.43 | Harbor Drive in Sioux City | Iowa 475 (later Iowa 970) in Sergeant Bluff | 01942-01-011942 | 01974-01-011974 | Airport access road |
| Iowa 379 | 4.59 | 7.39 | Joice | Iowa 105 near Lake Mills | 01942-01-011942 | 01980-01-011980 | Spur route |
| Iowa 380 | 1.30 | 2.09 | Ottumwa Regional Airport | US 63 near Ottumwa | 01943-01-011943 | 01969-01-011969 | Renumbered Iowa 389 when I-380 was designated |
| Iowa 381 | 1.10 | 1.77 | Iowa 84 near Cedar Rapids | US 218 (now Club Road) near Cedar Rapids | 01943-01-011943 | 01953-01-011953 | Airport access road; now Wright Brothers Boulevard |
| Iowa 381 | 0.67 | 1.08 | Iowa 254 near Rake | Rake | 01954-01-011954 | 01980-01-011980 | Spur route |
| Iowa 382 | 4.792 | 7.712 | Lake MacBride State Park | Iowa 1 in Solon | 01943-01-011943 | 02003-01-012003 | Park access road |
| Iowa 383 | 1.311 | 2.110 | US 69 near Randall | Randall | 01944-01-011944 | 02003-01-012003 | Spur route |
| Iowa 384 | 1.231 | 1.981 | Iowa 25 in Guthrie County | Springbrook State Park | 01944-01-011944 | 02003-01-012003 | Park access road |
| Iowa 385 | 3.151 | 5.071 | Pacific Junction | US 34 / US 275 in Glenwood | 01945-01-011945 | 02003-01-012003 | Spur route |
| Iowa 386 | 2.685 | 4.321 | US 52 / Iowa 3 near Sageville | US 52 / Iowa 3 / Iowa 32 near Dubuque | 01946-01-011946 | 02003-01-012003 | |
| Iowa 387 | 1.04 | 1.67 | US 65 near Zearing | Zearing | 01946-01-011946 | 01950-01-011950 | Spur route; replaced by an extended Iowa 317 |
| Iowa 387 | 0.52 | 0.84 | Davenport Municipal Airport | US 61 3 miles north of Davenport | 01951-01-011951 | 01979-01-011979 | Airport access road |
| Iowa 388 | 0.35 | 0.56 | Calumet | US 59 at Calumet | 01946-01-011946 | 01980-01-011980 | Spur route |
| Iowa 389 | 0.82 | 1.32 | Wild Cat Den State Park | Iowa 22 | 01946-01-011946 | 01962-01-011962 | Park access road |
| Iowa 389 | 1.25 | 2.01 | Ottumwa Regional Airport | US 63 near Ottumwa | 01969-01-011969 | 01997-01-011997 | Decommissioned when the first section of Ottumwa bypass opened |
| Iowa 390 | 0.74 | 1.19 | Marathon | Iowa 10 near Marathon | 01946-01-011946 | 01980-01-011980 | Spur route |
| Iowa 390 | 2.113 | 3.401 | South of Plainfield | North of Plainfield | 02002-01-012002 | 02003-01-012003 | Former section of US 218 |
| Iowa 391 | 0.50 | 0.80 | Clinton Municipal Airport | US 30 near Clinton | 01946-01-011946 | 01972-01-011972 | Airport access road; now 60th Street |
| Iowa 392 | 0.63 | 1.01 | Dubuque Regional Airport | US 61 near Dubuque | 01946-01-011946 | 01974-01-011974 | Airport access road; now Airport Road |
| Iowa 392 | 3.09 | 4.97 | Iowa 163 in Prairie City | Iowa 163 in Prairie City | 01998-01-011998 | 02000-01-012000 | Former section of Iowa 163 |
| Iowa 393 | 2.40 | 3.86 | Ionia | US 18 near Ionia | 01948-01-011948 | 01980-01-011980 | Spur route |
| Iowa 394 | 2.27 | 3.65 | Iowa 2 near Denmark | Iowa Army Ammunition Plant southern entrance | 01948-01-011948 | 01980-01-011980 | Spur route |
| Iowa 394 | 10.454 | 16.824 | Route B at St. Francisville, Mo. | US 218 near Donnellson | 01980-01-011980 | 02005-01-012005 | Replaced by Iowa 27 |
| Iowa 395 | 0.53 | 0.85 | Iowa 330 near Melbourne | Melbourne | 01948-01-011948 | 01983-01-011983 | Spur route; section in Melbourne removed 1980 |
| Iowa 396 | 0.89 | 1.43 | Iowa 14 in Newton | US 6 in Newton | 01948-01-011948 | 01954-01-011954 | Now 19th Avenue and 8th Street |
| Iowa 396 | 0.52 | 0.84 | Iowa 175 near Farnhamville | Farnhamville | 01954-01-011954 | 01980-01-011980 | Spur route |
| Iowa 397 | 0.69 | 1.11 | Paton | Iowa 144 near Paton | 01948-01-011948 | 01991-01-011991 | Spur route |
| Iowa 398 | 1.24 | 2.00 | Brooklyn | US 6 near Brooklyn | 01956-01-011956 | 01980-01-011980 | Spur route |
| Iowa 399 | 0.65 | 1.05 | Iowa 74 near Palo | Palo | 01956-01-011956 | 01964-01-011964 | Spur route |
| Iowa 400 | 4.54 | 7.31 | Truro | I-35 near Truro | 01957-01-011957 | 01980-01-011980 | Spur route; not completed until 1958 |
| Iowa 401 | 5.32 | 8.56 | Camp Dodge | US 6 in Des Moines | 01958-01-011958 | 01991-01-011991 | Replaced by an extended Iowa 28 south of I-80; rest decommissioned |
| Iowa 402 | 20.9 | 33.6 | Iowa 8 near Dysart | Iowa 412 in Waterloo | 01957-01-011957 | 01968-12-311968 | Replaced by Iowa 21 |
| Iowa 403 | 0.70 | 1.13 | Cushing | US 20 near Cushing | 01958-01-011958 | 01980-01-011980 | Spur route |
| Iowa 403 | 0.477 | 0.768 | SD 48 near Akron | Iowa 12 in Akron | 01980-01-011980 | 02003-01-012003 | |
| Iowa 404 | 1.391 | 2.239 | Montrose | US 61 near Montrose | 01960-01-011960 | 02003-01-012003 | Spur route |
| Iowa 404 | 1.629 | 2.622 | Iowa 3 in Le Mars | US 75 at Le Mars | 02006-01-012006 | current | Section of US 75 Business in Le Mars |
| Iowa 405 | 0.249 | 0.401 | Lone Tree | Iowa 22 near Lone Tree | 01958-01-011958 | 02003-01-012003 | Spur route; section in Lone Tree removed 1980 |
| Iowa 406 | 2.275 | 3.661 | US 34 near West Burlington | Burlington | 01957-01-011957 | 02003-01-012003 | Formerly Iowa 80; spur route |
| Iowa 407 | 0.47 | 0.76 | Iowa 99 in Oakville | Oakville | 01957-01-011957 | 01967-01-011967 | Formerly Iowa 7; spur route |
| Iowa 408 | 7.40 | 11.91 | US 169 near Lu Verne | Lu Verne | 01957-01-011957 | 01980-01-011980 | Spur route |
| Iowa 409 | 0.41 | 0.66 | US 18 near Garner | Garner | 01957-01-011957 | 01968-01-011968 | Formerly Iowa 35; spur route |
| Iowa 410 | 2.157 | 3.471 | Backbone State Park | Iowa 3 / Iowa 13 near Strawberry Point | 01958-01-011958 | 02003-01-012003 | Park access road |
| Iowa 411 | 0.98 | 1.58 | US 6 at Marengo | CR F15 north of Marengo | 01957-01-011957 | 01964-01-011964 | Spur route |
| Iowa 412 | 4.72 | 7.60 | US 63 in Waterloo | US 218 in Waterloo | 01960-01-011960 | 01983-01-011983 | San Marnan Drive in Waterloo |
| Iowa 413 | 3.95 | 6.36 | US 20 in Fort Dodge | Fort Dodge Airport | 01960-01-011960 | 01980-01-011980 | Spur route; continued north to Iowa 320 near Badger until Iowa 320 was decommissioned |
| Iowa 414 | 6.12 | 9.85 | US 6 near Lewis | US 71 near Atlantic | 01958-01-011958 | 01972-01-011972 | Former section of Iowa 92; was Iowa 100 for a month in 1958 |
| Iowa 415 | 16.857 | 27.129 | US 6 in Des Moines | Iowa 141 near Granger | 01959-01-011959 | current | |
| Iowa 416 | 4.89 | 7.87 | Centralia | US 20 | 01959-01-011959 | 01969-01-011969 | Former section of US 20; sections were renumbered Iowa 418 and Iowa 420 in 1960 |
| Iowa 417 | 5.38 | 8.66 | US 67 near Riverdale | US 67 near LeClaire | 01960-01-011960 | 01968-01-011968 | Former section of US 67 |
| Iowa 418 | 0.85 | 1.37 | Farley | US 20 | 01960-01-011960 | 01968-01-011968 | Former section of US 20 |
| Iowa 419 | 1.038 | 1.670 | Victor | US 6 / Iowa 21 near Victor | 01962-01-011962 | 02003-01-012003 | Spur route |
| Iowa 420 | 2.37 | 3.81 | Iowa 136 in Dyersville | US 20 | 01960-01-011960 | 01969-01-011969 | Former section of US 20 |
| Iowa 421 | 3.260 | 5.246 | — | — | 02000-01-012000 | 02003-01-012003 | Former section of US 61 northeast of Muscatine |
| Iowa 422 | 0.52 | 0.84 | US 169 near Burt | Burt | 01964-01-011964 | 01976-01-011976 | Spur route; renumbered Iowa 969 |
| Iowa 424 | 0.44 | 0.71 | Iowa 111 in Britt | US 18 near Britt | 01961-01-011961 | 01980-01-011980 | Spur route |
| Iowa 424 | 2.802 | 4.509 | South of Swedesburg | US 218 near Olds | 01999-01-011999 | 02003-01-012003 | Former section of US 218 |
| Iowa 426 | 0.52 | 0.84 | Iowa 92 near Rose Hill | Rose Hill | 01960-01-011960 | 01980-01-011980 | Former section of Iowa 92 |
| Iowa 428 | 1.21 | 1.95 | Anamosa | US 151 near Anamosa | 01965-01-011965 | 01980-01-011980 | Spur route |
| Iowa 428 | 6.140 | 9.881 | Maquoketa Caves State Park | US 61 near Maquoketa | 01980-01-011980 | 02003-01-012003 | Park access road |
| Iowa 431 | 3.183 | 5.123 | US 218 near Waverly | Iowa 3 in Waverly | 01998-01-011998 | 02001-01-012001 | Section of US 218 Business in Waverly |
| Iowa 431 | 1.920 | 3.090 | US 30 near Le Grand | US 30 near Le Grand | 02004-01-012004 | 02014-01-012014 | Former section of US 30 |
| Iowa 432 | 1.9 | 3.1 | Iowa 163 in Oskaloosa | Iowa 92 in Oskaloosa | 01998-01-011998 | 02003-01-012003 | Former section of Iowa 163 |
| Iowa 434 | 8.993 | 14.473 | US 34 in Danville | US 34 in West Burlington | 02005-01-012005 | 02008-01-012008 | Former section of US 34 |
| Iowa 437 | 0.299 | 0.481 | Dead end near Iowa 137 in Eddyville | Dead end near Iowa 342 in Eddyville | 02005-01-012005 | 02008-01-012008 | 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 | 02003-01-012003 | current | Section of US 218 Business in Mount Pleasant |
| Iowa 450 | 0.268 | 0.431 | Iowa 10 at Alton | Iowa 60 at Alton | 02005-01-012005 | current | 450th Street |
| Iowa 460 | 7.240 | 11.652 | — | — | 02004-01-012004 | 02007-01-012007 | 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 | 02010-01-012010 | current | US 61 Business in Davenport |
| Iowa 463 | 2.3 | 3.7 | US 63 near Frederika | US 63 near Frederika | 02009-01-012009 | 02010-01-012010 | Former section of US 63 |
| Iowa 470 | 0.695 | 1.118 | US 75 in Merrill | US 75 in Merrill | 02011-01-012011 | current | Former section of US 75 |
| Iowa 471 | 11.160 | 17.960 | Iowa 175 near Lake View | US 20 / US 71 near Early | 02015-01-012015 | current | Formerly US 71 in Sac County |
| Iowa 475 | 31.79 | 51.16 | Business US 75 in Sioux City | Iowa 175 in Onawa | 01969-01-011969 | 01976-01-011976 | Former section of US 75; renumbered Iowa 970 |
| Iowa 478 | 0.755 | 1.215 | Iowa 24 in New Hampton | North of New Hampton | 02002-01-012002 | 02003-01-012003 | Former section of US 63 |
| Iowa 903 | 0.13 | 0.21 | Just south of Iowa 163 near Leighton | Just south of Iowa 163 near Leighton | 02011-01-012011 | 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 | 02008-01-012008 | 02011-01-012011 | 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 | 02016-01-012016 | 02023-01-012023 | Formerly US 6 through Council Bluffs |
| Iowa 912 | 0.22 | 0.35 | — | — | 01997-01-011997 | 01999-01-011999 | Former section of Iowa 141 |
| Iowa 913 | 1.686 | 2.713 | — | — | 01996-01-011996 | 01997-01-011997 | Former section of US 61 |
| Iowa 914 | 1.01 | 1.63 | Storm Lake city limit boundary | Iowa 7 in Storm Lake | 01996-01-011996 | 02001-01-012001 | Former section of US 71 |
| Iowa 915 | .27 | 0.43 | Iowa 3 / Iowa 150 in Oelwein | Iowa 3 / Iowa 150 in Oelwein | 01986-01-011986 | 01990-01-011990 | Former section of Iowa 3/Iowa 150 concurrency |
| Iowa 915 | 3.7 | 6.0 | — | — | 01993-01-011993 | 01994-01-011994 | Former section of Iowa 415 in Ankeny |
| Iowa 915 | .580 | 0.933 | Iowa 5 in Albia | Iowa 5 in Albia | 01995-01-011995 | 01997-01-011997 | Former section of Iowa 5 |
| Iowa 916 | 1.293 | 2.081 | Iowa 281 in Oelwein | Oelwein city limits | 01986-01-011986 | 02003-01-012003 | 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 | 01986-01-011986 | 02003-01-012003 | Former section of Iowa 22 |
| Iowa 918 | 1.119 | 1.801 | Iowa 16 near Eldon | Iowa 16 in Eldon | 01984-01-011984 | 02003-01-012003 | Former section of Iowa 16; street signs said "Hwy 918" |
| Iowa 919 | 0.39 | 0.63 | Iowa 363 in Urbana | Walnut Street in Urbana | 01984-01-011984 | 01995-01-011995 | Former section of Iowa 363; now Ash Street and Wood Street |
| Iowa 920 | 12.560 | 20.213 | Center Point | Iowa 150 near Urbana | 01984-01-011984 | 02003-01-012003 | Former section of Iowa 150 |
| Iowa 921 | 11.75 | 18.91 | Iowa 920 in Center Point | Hiawatha | 01984-01-011984 | 01985-01-011985 | Former section of Iowa 150 |
| Iowa 921 | 2.505 | 4.031 | US 6 / Iowa 1 in Iowa City | US 218 in Iowa City | 01985-01-011985 | 02003-01-012003 | Former section of US 218 |
| Iowa 922 | 1.27 | 2.04 | US 61 in Muscatine | Iowa 22 in Muscatine | 01984-01-011984 | 01986-01-011986 | 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 | 01987-01-011987 | 01988-01-011988 | Former section of Iowa 149 |
| Iowa 922 | 8.862 | 14.262 | US 151 at Cedar Rapids | Iowa 100 in Cedar Rapids | 01989-01-011989 | current | US 151 Business in Cedar Rapids |
| Iowa 923 | 8.819 | 14.193 | — | — | 01982-01-011982 | 02003-01-012003 | Former section of US 218; had three sections |
| Iowa 924 | 4.00 | 6.44 | Iowa 175 near Farnhamville | Webster–Greene County Line | 01980-01-011980 | 01982-01-011982 | Now County Road P29 |
| Iowa 924 | 2.24 | 3.60 | US 52 in Dubuque | Dead end in Dubuque | 01983-01-011983 | 01992-01-011992 | Former section of US 61/US 151 concurrency |
| Iowa 924 | 0.665 | 1.070 | US 61 near Montrose | Dead end in Montrose | 01994-01-011994 | 02003-01-012003 | Formerly Iowa 998; former section of US 61 |
| Iowa 925 | 26.259 | 42.260 | I-80 / US 6 in Adair | US 6 near Dexter | 01980-01-011980 | 02003-01-012003 | Former section of US 6 |
| Iowa 926 | 3.18 | 5.12 | US 6 | Altoona east city limit boundary | 01980-01-011980 | 01988-01-011988 | 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 | 01990-01-011990 | 02014-01-012014 | |
| Iowa 927 | 19.017 | 30.605 | US 6 / Iowa 38 in Wilton | I-280 / US 6 near Davenport | 01980-01-011980 | 02003-01-012003 | Former section of US 6; was signed in 1989 |
| Iowa 928 | 20.168 | 32.457 | Iowa 17 near Webster City | CR D20 near Williams | 01980-01-011980 | 02003-01-012003 | Former section of US 20 |
| Iowa 929 | 0.789 | 1.270 | Murray city limits | Maple Street in Murray | 01980-01-011980 | 02003-01-012003 | Former section of Iowa 152 |
| Iowa 930 | 1.738 | 2.797 | US 30 near Ames | Boone–Story county line | 01972-01-011972 | current | Former section of US 30 |
| Iowa 931 | 1.2 | 1.9 | Iowa 13 in Coggon | Iowa 13 near Coggon | 01976-01-011976 | 01978-01-011978 | Former section of Iowa 13 |
| Iowa 931 | 8.962 | 14.423 | I-35 in Ankeny | US 65 in Polk County | 01980-01-011980 | 02003-01-012003 | |
| Iowa 932 | 0.193 | 0.311 | Ryan city limits | Iowa 13 in Ryan | 01976-01-011976 | 02003-01-012003 | Former section of Iowa 13 |
| Iowa 933 | 0.74 | 1.19 | Iowa 141 in Perry | Iowa 141 in Perry | 01976-01-011976 | 01984-01-011984 | Former section of Iowa 141 |
| Iowa 933 | 0.21 | 0.34 | — | — | 01985-01-011985 | 01999-01-011999 | Former section of Iowa 58 just south of US 20 |
| Iowa 934 | 1.07 | 1.72 | US 61 near Burlington | US 61 near Burlington | 01976-01-011976 | 01980-01-011980 | Former section of US 61; now Memorial Park Road |
| Iowa 934 | 1.14 | 1.83 | Dallas–Polk county line | I-35 in Des Moines | 01981-01-011981 | 01989-01-011989 | Former section of Iowa 90 |
| Iowa 934 | 4.76 | 7.66 | US 20 near Moorland | US 169 in Fort Dodge | 01990-01-011990 | 01991-01-011991 | Former section of US 20 |
| Iowa 934 | 0.19 | 0.31 | — | — | 01992-01-011992 | 01994-01-011994 | 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 | 01998-01-011998 | 02016-01-012016 | Was an unsigned highway |
| Iowa 935 | 0.77 | 1.24 | — | — | 01976-01-011976 | 01981-01-011981 | Former section of US 34 parallel to Business US 34 in Burlington |
| Iowa 935 | 1.492 | 2.401 | I-29 | Mills–Pottawattamie county line | 01982-01-011982 | 02003-01-012003 | Former section of Iowa 370 |
| Iowa 936 | 0.087 | 0.140 | east city limits of West Burlington | west city limits of Burlington | 01976-01-011976 | 01995-01-011995 | Former section of Iowa 406 |
| Iowa 936 | 0.275 | 0.443 | Iowa 92 near Ainsworth | Iowa 923 near Ainsworth | 01997-01-011997 | 02003-01-012003 | Former section of Iowa 92 |
| Iowa 937 | 4.23 | 6.81 | Iowa 2 near Bloomfield | Iowa 2 near Bloomfield | 01976-01-011976 | 01977-01-011977 | Former section of Iowa 2 |
| Iowa 937 | 0.460 | 0.740 | Iowa 141 near Perry | US 169 near Perry | 01977-01-011977 | 02003-01-012003 | Former section of Iowa 141 |
| Iowa 938 | 1.57 | 2.53 | Iowa 947 near Manchester | Manchester Fish Hatchery | 01976-01-011976 | 01980-01-011980 | Former Iowa 116 |
| Iowa 938 | 0.460 | 0.740 | Union Street in Unionville | Unionville south city limit boundary | 01980-01-011980 | 02003-01-012003 | Former section of Iowa 369 |
| Iowa 939 | 6.76 | 10.88 | US 65 | Iowa 2 near Corydon | 01976-01-011976 | 01980-01-011980 | Former section of Iowa 2 |
| Iowa 939 | 18.931 | 30.466 | Iowa 187 near Masonville | Black Hawk–Buchanan county line | 01980-01-011980 | 02003-01-012003 | Former section of US 20 |
| Iowa 940 | 2.51 | 4.04 | — | — | 01976-01-011976 | 01980-01-011980 | 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 | 01981-01-011981 | 02003-01-012003 | |
| Iowa 941 | 2.99 | 4.81 | County Road J18 in Moravia | Iowa 5 near Moravia | 01976-01-011976 | 01980-01-011980 | Former section of Iowa 5 |
| Iowa 941 | 6.38 | 10.27 | US 30 / US 218 in Cedar Rapids | US 30 / US 218 in Cedar Rapids | 01981-01-011981 | 01987-01-011987 | Former section of US 30/US 218 concurrency |
| Iowa 941 | 1.12 | 1.80 | 5th Avenue Southwest in Epworth | Bierman Road in Epworth | 01988-01-011988 | 01990-01-011990 | Former section of US 20 |
| Iowa 941 | 12.953 | 20.846 | I-35 near Williams | Iowa Falls city limits | 01991-01-011991 | 02003-01-012003 | Former section of US 20 |
| Iowa 942 | 5.70 | 9.17 | Iowa 5 near Moravia | County Road J18 in Moravia | 01976-01-011976 | 01980-01-011980 | Former section of Iowa 5; had another section south of Albia |
| Iowa 942 | 0.466 | 0.750 | Vine Street in Woodburn | Woodburn city limits | 01980-01-011980 | 02003-01-012003 | Former section of Iowa 104 |
| Iowa 943 | 0.69 | 1.11 | — | — | 01974-01-011974 | 01980-01-011980 | Former section of Iowa 13 in Central City |
| Iowa 943 | 0.43 | 0.69 | 1st Street in Galva | Galva city limits | 01980-01-011980 | 01987-01-011987 | Former section of Iowa 328 |
| Iowa 943 | 0.48 | 0.77 | — | — | 01988-01-011988 | 01990-01-011990 | Former Iowa 12 ramp in Sioux City; road destroyed 1990s |
| Iowa 943 | 1.82 | 2.93 | US 63 in Denver | US 63 in Denver | 01994-01-011994 | 01995-01-011995 | Former section of US 63 |
| Iowa 944 | 0.99 | 1.59 | Iowa 13 in Manchester | Iowa 13 in Manchester | 01976-01-011976 | 01980-01-011980 | Former section of Iowa 13 |
| Iowa 944 | 0.553 | 0.890 | US 61 / Iowa 2 in Fort Madison | Fort Madison city limits | 01980-01-011980 | 02003-01-012003 | Former section of Iowa 88 |
| Iowa 945 | 4.599 | 7.401 | I-80 near Altoona | Iowa 931 in Polk County | 01980-01-011980 | 02003-01-012003 | |
| Iowa 946 | 2.72 | 4.38 | Luana city limits | US 18 / US 52 in Monona | 01976-01-011976 | 01980-01-011980 | Former section of US 18/US 52 concurrency; had two sections separated by the city limits of Monona |
| Iowa 946 | 0.07 | 0.11 | US 218 in St. Ansgar | Park Street in St. Ansgar | 01988-01-011988 | 01989-01-011989 | 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 | 01991-01-011991 | current | Provides direct access between US 20 and US 52 / US 61 / US 151 |
| Iowa 947 | 23.75 | 38.22 | Iowa 187 | Dyersville city limits | 01976-01-011976 | 01981-01-011981 | Former section of US 20 |
| Iowa 947 | 0.45 | 0.72 | Zearing city limits | Pearl Street in Zearing | 01981-01-011981 | 01986-01-011986 | Former section of Iowa 317 |
| Iowa 947 | 4.74 | 7.63 | Iowa 57 in Cedar Falls | Greenhill Road in Waterloo | 01989-01-011989 | 01992-01-011992 | Former section of US 218 |
| Iowa 947 | 2.47 | 3.98 | Iowa 70 in Columbus Junction | Market Street in Columbus City | 01994-01-011994 | 02003-01-012003 | Former section of Iowa 70; only the 0.671 miles in Columbus City were left on December 1, 1997 |
| Iowa 948 | 5.08 | 8.18 | DeWitt city limits | US 30 near DeWitt | 01975-01-011975 | 01987-01-011987 | Former section of US 30 |
| Iowa 948 | .30 | 0.48 | US 61 / US 151 in Dubuque | Iowa 959 in Dubuque | 01992-01-011992 | 01993-01-011993 | Former section of US 61/US 151 concurrency |
| Iowa 949 | 2.275 | 3.661 | Glenwood city limits | US 34 / US 275 near Glenwood | 01974-01-011974 | 02003-02-182003 | Formerly US 34 Business |
| Iowa 950 | 3.45 | 5.55 | US 6 / US 65 in Altoona | iowa 163 in Pleasant Hill | 01980-01-011980 | 01994-01-011994 | Now 34th Avenue/56th Street |
| Iowa 951 | 2.65 | 4.26 | US 34 west of Osceola | US 34 near Osceola | 01976-01-011976 | 01980-01-011980 | Former section of US 34 |
| Iowa 951 | 3.15 | 5.07 | Carbon city limits | Iowa 148 | 01983-01-011983 | 01993-01-011993 | Former Section of Iowa 95 |
| Iowa 952 | 1.8 | 2.9 | US 61 in Burlington | Central avenue in Burlington | 01976-01-011976 | 01976-01-011976 | Former section of US 34 |
| Iowa 952 | 0.18 | 0.29 | — | — | 01978-01-011978 | 01982-01-011982 | Former section of US 67 north of Clinton |
| Iowa 952 | 0.112 | 0.180 | US 151 near Cascade | Reiter Road near Cascade | 01992-01-011992 | 02003-01-012003 | Former section of US 151 |
| Iowa 953 | 0.89 | 1.43 | Iowa 38 near Muscatine | Iowa 38 in Muscatine | 01976-01-011976 | 01980-01-011980 | Former section of Iowa 38 |
| Iowa 953 | 0.08 | 0.13 | Iowa 149 in North English | Dead end in North English | 01988-01-011988 | 01994-01-011994 | Former section of Iowa 149 |
| Iowa 953 | 1.0 | 1.6 | Iowa 5 in West Des Moines | Browns Woods Road in West Des Moines | 01995-01-011995 | 01996-01-011996 | Former section of Iowa 28 |
| Iowa 954 | 0.773 | 1.244 | US 61 near Maquoketa | Maquoketa city limits | 01967-01-011967 | 02003-01-012003 | 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 | 01971-01-011971 | 02003-01-012003 | Former section of US 61 |
| Iowa 956 | 16.776 | 26.998 | CR F55 at Davenport | US 61 north of DeWitt | 01976-01-011976 | 02003-01-012003 | Former section of US 61 |
| Iowa 957 | 3.33 | 5.36 | US 63 near Bloomfield | US 63 near Bloomfield | 01976-01-011976 | 01977-01-011977 | Former section of US 63 |
| Iowa 957 | 0.062 | 0.100 | — | — | 01988-01-011988 | 02003-01-012003 | Former section of Iowa 22 |
| Iowa 958 | 1.610 | 2.591 | Ottumwa city limits | US 63 south of Ottumwa | 01965-01-011965 | 02003-01-012003 | Former section of US 63 |
| Iowa 959 | 1.27 | 2.04 | US 65 / US 69 in Des Moines | Des Moines city limits | 01970-01-011970 | 01981-01-011981 | Former section of US 65/US 69 concurrency |
| Iowa 959 | 1.29 | 2.08 | US 61 / US 151 in Dubuque | US 61 / US 151 & US 52 in Dubuque | 01992-01-011992 | 01993-01-011993 | Former section of US 61/US 151 concurrency |
| Iowa 960 | 1.58 | 2.54 | Clarinda city limits | Iowa 2 near Clarinda | 01973-01-011973 | 01982-01-011982 | Former section of Iowa 2 |
| Iowa 960 | 1.11 | 1.79 | — | — | 01982-01-011982 | 01986-01-011986 | Former section of US 61 |
| Iowa 960 | 4.7 | 7.6 | — | — | 01993-01-011993 | 01994-01-011994 | 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 | 02006-01-012006 | 02007-01-012007 | Former section of Iowa 60 |
| Iowa 961 | 0.56 | 0.90 | Villisca city limits | US 71 near Villisca | 01976-01-011976 | 01980-01-011980 | Former section of US 71 |
| Iowa 961 | 1.08 | 1.74 | US 61 / US 151 in Dubuque | US 20 in Dubuque (southbound), Iowa 946 in Dubuque (northbound) | 01991-01-011991 | 01993-01-011993 | Former section of US 151 and US 61 |
| Iowa 961 | 0.50 | 0.80 | — | — | 01994-01-011994 | 01996-01-011996 | Former section of US 61 in Wever |
| Iowa 961 | 3.613 | 5.815 | Iowa 2 in Fort Madison | US 61 at Fort Madison | 02011-01-012011 | 02013-01-012013 | Section of US 61 Business in Fort Madison |
| Iowa 962 | 0.11 | 0.18 | US 218 near Ainsworth | County Road W64 near Ainsworth | 01994-01-011994 | 01997-01-011997 | Former section of US 218 |
| Iowa 963 | 4.139 | 6.661 | US 151 near Key West | US 61 / US 151 in Dubuque | 01971-01-011971 | 02003-01-012003 | Former section of US 151 and US 61 |
| Iowa 964 | 4.704 | 7.570 | Iowa 92 near Knoxville | Iowa 92 near Knoxville | 01977-01-011977 | 01996-01-011996 | Former section of Iowa 92 |
| Iowa 965 | 3.29 | 5.29 | — | — | 01976-01-011976 | 01980-01-011980 | Former section of US 52 |
| Iowa 965 | 0.519 | 0.835 | US 6 in Coralville | I-80 in Coralville | 01985-01-011985 | current | Former section of US 218; extended to Cedar Rapids until 2003 |
| Iowa 966 | 4.89 | 7.87 | Centralia | US 20 | 01976-01-011976 | 01996-01-011996 | 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 | 01976-01-011976 | 02003-01-012003 | Former Iowa 418, and before that, was a section of US 20 |
| Iowa 968 | 2.37 | 3.81 | Iowa 136 in Dyersville | US 20 | 01976-01-011976 | 01989-01-011989 | Former Iowa 420, and before that, was a section of US 20 |
| Iowa 968 | 5.36 | 8.63 | Iowa 163 in Pella | Iowa 163 in Pella | 01993-01-011993 | 01994-01-011994 | Former section of Iowa 163 |
| Iowa 969 | 0.52 | 0.84 | US 169 near Burt | Burt | 01976-01-011976 | 01980-01-011980 | Spur route; former Iowa 422 |
| Iowa 969 | 4.0 | 6.4 | US 218 near Janesville | US 218 near Janesville | 01993-01-011993 | 01994-01-011994 | Former section of US 218 |
| Iowa 970 | 31.79 | 51.16 | Business US 75 in Sioux City | Iowa 175 in Onawa | 01976-01-011976 | 02003-01-012003 | Former section of US 75 |
| Iowa 971 | 10.78 | 17.35 | Iowa 2 | US 59 in Shenandoah | 01975-01-011975 | 01979-01-011979 | Former section of Iowa 2 |
| Iowa 971 | 1.802 | 2.900 | US 69 in Lake Mills | Winnebago–Worth county line | 01993-01-011993 | 02003-01-012003 | 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 | 01969-01-011969 | 01974-01-011974 | 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 | 01974-01-011974 | 01974-01-011974 | Former section of US 34; renumbered Iowa 978 to avoid confusion with the other Iowa 972 |
| Iowa 972 | 10.17 | 16.37 | Iowa 92 / US 169 in Winterset | US 169 | 01974-01-011974 | 01980-01-011980 | Former section of US 169 |
| Iowa 972 | 1.877 | 3.021 | Northwood city limits | Northwood city limits | 01993-01-011993 | 02003-01-012003 | Former section of Iowa 105 |
| Iowa 973 | 1.95 | 3.14 | I-29 in Council Bluffs | US 6 in Council Bluffs | 01969-01-011969 | 01971-01-011971 | Former section of US 75 |
| Iowa 973 | 10.32 | 16.61 | US 71 near Atlantic | Iowa 148 in Anita | 01972-01-011972 | 01973-01-011973 | Former section of US 6; became part of an extended Iowa 83 |
| Iowa 973 | 1.49 | 2.40 | Iowa 92 in Winterset | Iowa 972 in Winterset | 01976-01-011976 | 01980-01-011980 | Former section of Iowa 92 |
| Iowa 973 | 0.65 | 1.05 | St. Ansgar city limits | US 218 in St. Ansgar | 01993-01-011993 | 02001-01-012001 | Former section of Iowa 105 |
| Iowa 974 | 5.09 | 8.19 | O'Connor Road northwest of Mount Vernon | Mount Vernon city limits | 01965-01-011965 | 01980-01-011980 | Former section of Iowa 150 |
| Iowa 975 | 1.33 | 2.14 | North city limits of Marengo | CR F15 north of Marengo | 01964-01-011964 | 01974-01-011974 | Former section of Iowa 411 |
| Iowa 975 | 1.55 | 2.49 | Iowa 964 in Knoxville | Iowa 5 / Iowa 92 in Knoxville | 01978-01-011978 | 01986-01-011986 | Former section of Iowa 5/Iowa 92 concurrency |
| Iowa 975 | 0.13 | 0.21 | — | — | 01995-01-011995 | 01995-01-011995 | Former section of US 275/Iowa 333 concurrency east of Hamburg |
| Iowa 976 | 2.00 | 3.22 | US 218 | Mount Pleasant city limits | 01974-01-011974 | 01980-01-011980 | Former section of US 218; formerly Iowa 972 |
| Iowa 976 | 0.22 | 0.35 | Marshalltown city limits | Governor Road east of Marshalltown | 01996-01-011996 | 01997-01-011997 | Former section of US 30 |
| Iowa 976 | 0.879 | 1.415 | — | — | 01997-01-011997 | 02003-01-012003 | Former section of US 30 |
| Iowa 977 | 2.007 | 3.230 | US 59 in Cherokee | Iowa 3 near Cherokee | 01962-01-011962 | 02003-01-012003 | Former section of Iowa 3 |
| Iowa 978 | 2.77 | 4.46 | Iowa 44 in Whittemore | Iowa 358 in Whittemore | 01962-01-011962 | 01965-01-011965 | Former section of Iowa 358 |
| Iowa 978 | 2.772 | 4.461 | I-29 / US 34 near Glenwood | Iowa 385 near Pacific Junction | 01974-01-011974 | 02003-02-182003 | Former section of US 34; formerly Iowa 972 |
| Iowa 979 | 19.80 | 31.87 | Iowa City limits | Iowa 38 | 01961-01-011961 | 02003-01-012003 | Former section of Iowa 1 |
| Iowa 980 | 0.77 | 1.24 | US 34 near Ottumwa | Ottumwa city limits | 01967-01-011967 | 01980-01-011980 | Former section of US 34; formerly US 34 Alternate |
| Iowa 981 | 0.44 | 0.71 | Iowa 150 near Fayette | Fayette city limits | 01967-01-011967 | 01980-01-011980 | 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 | 01995-01-011995 | 01996-01-011996 | Former section of US 34 |
| Iowa 982 | 0.30 | 0.48 | Dubuque–Jones County Line | Iowa 136 near Cascade | 01961-01-011961 | 01965-01-011965 | Former section of Iowa 136 |
| Iowa 982 | 27.787 | 44.719 | Smithland city limits | Sioux City city limits | 01967-01-011967 | 02003-01-012003 | Former section of Iowa 141; formerly Iowa 994 |
| Iowa 983 | 0.99 | 1.59 | Iowa 989 | US 34 / Iowa 213 | 01961-01-011961 | 01964-01-011964 | Former section of Iowa 213 |
| Iowa 983 | 0.81 | 1.30 | US 34 west of Chariton | US 34 east of Chariton | 01967-01-011967 | 01980-01-011980 | 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 | 01998-01-011998 | 01998-01-011998 | Former section of Iowa 5 |
| Iowa 984 | 2.24 | 3.60 | Bettendorf city limits | US 67 in Le Claire | 01968-01-011968 | 01982-01-011982 | Former section of Iowa 417 |
| Iowa 985 | 1.00 | 1.61 | US 63 north of Oskaloosa | US 63 north of Oskaloosa | 01961-01-011961 | 01965-01-011965 | Former section of US 63; decommissioned by 1965 |
| Iowa 985 | 7.66 | 12.33 | Sioux City limits | I-29 in Sioux City | 01969-01-011969 | 01973-01-011973 | Former section of Iowa 7 |
| Iowa 985 | 1.927 | 3.101 | US 52 near Bellevue State Park | US 52 near Bellevue | 01980-01-011980 | 02003-01-012003 | Park access road; former section of US 52 |
| Iowa 986 | 4.86 | 7.82 | Harrison–Monona county line | Iowa 301 in River Sioux | 01968-01-011968 | 01986-01-011986 | Former section of US 75 |
| Iowa 987 | 4.45 | 7.16 | US 63 / Iowa 412 in Waterloo | Hudson city limits | 01961-01-011961 | 01964-01-011964 | Former section of US 63 |
| Iowa 988 | 0.16 | 0.26 | Iowa 58 near Hudson | Hudson city limits | 01961-01-011961 | 01964-01-011964 | Former section of US 63 |
| Iowa 988 | 2.312 | 3.721 | I-29 / I-680 near Crescent | Iowa 183 in Crescent | 01975-01-011975 | 02003-01-012003 | |
| Iowa 989 | 17.76 | 28.58 | Albia city limits | US 34 near Ottumwa | 01961-01-011961 | 01964-01-011964 | Former section of US 34 |
| Iowa 990 | 0.27 | 0.43 | Iowa 150 near Fayette | Fayette city limits | 01961-01-011961 | 01965-01-011965 | Former section of Iowa 150 |
| Iowa 991 | 0.44 | 0.71 | Fayette city limits | Iowa 150 near Fayette | 01961-01-011961 | 01967-01-011967 | Former section of Iowa 150; renumbered Iowa 981 |
| Iowa 992 | 8.81 | 14.18 | Wesley city limits | Britt city limits | 01961-01-011961 | 01965-01-011965 | Former section of US 18 |
| Iowa 993 | 3.52 | 5.66 | US 18 near Wesley | Wesley city limits | 01961-01-011961 | 01965-01-011965 | Former section of US 18 |
| Iowa 994 | 27.787 | 44.719 | Smithland city limits | Sioux City city limits | 01961-01-011961 | 01967-01-011967 | Former section of Iowa 141; renumbered Iowa 982 |
| Iowa 995 | 0.56 | 0.90 | US 34 west of Chariton | Chariton city limits | 01961-01-011961 | 01967-01-011967 | Former section of US 34; renumbered Iowa 983 |
| Iowa 996 | 0.23 | 0.37 | Chariton city limits | US 34 east of Chariton | 01961-01-011961 | 01976-01-011976 | Former section of US 34; became a second section of Iowa 983 |
| Iowa 997 | 0.89 | 1.43 | US 169 / Iowa 5 near Fort Dodge | Fort Dodge city limits | 01961-01-011961 | 01970-01-011970 | Former section of Iowa 5 (now Iowa 7) |
| Iowa 998 | 0.67 | 1.08 | US 61 near Montrose | Dead end in Montrose | 01961-01-011961 | 01994-01-011994 | Former section of US 61; renumbered Iowa 924 |
| Iowa 999 | 2.22 | 3.57 | Spruce Street in College Springs | Iowa 333 near College Springs | 01961-01-011961 | 01980-01-011980 | Former section of Iowa 333 |
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