Iowa Population By County in 2017

Updated on January 29, 2024.

Based on the US Census Vintage data estimates, in 2017, the population of Iowa was 3,143,734. Among all Iowa counties, Polk had the highest population (480,962), followed by Linn (224,553), and Scott (172,691). Adams was the least populated county (3,655).

Hover over or click on the counties in the map below to see the populations. The data can also be found in a table below. You can use the table to sort, filter, and explore the data further.

You can see similar information for other states and by state for the United States.

See this for other years:
Iowa Population By County in 2017
Iowa Population By County in 2017
Items per page:
0 of 0
County Population % of State Population
Adair 7047 0.22
Adams 3655 0.12
Allamakee 13812 0.44
Appanoose 12367 0.39
Audubon 5550 0.18
Benton 25651 0.82
Black Hawk 132278 4.21
Boone 26498 0.84
Bremer 24861 0.79
Buchanan 21133 0.67
Buena Vista 20154 0.64
Butler 14593 0.46
Calhoun 9730 0.31
Carroll 20256 0.64
Cass 13155 0.42
Cedar 18488 0.59
Cerro Gordo 43030 1.37
Cherokee 11315 0.36
Chickasaw 12008 0.38
Clarke 9395 0.30
Clay 16151 0.51
Clayton 17647 0.56
Clinton 46926 1.49
Crawford 17065 0.54
Dallas 87219 2.77
Davis 8969 0.28
Decatur 7956 0.25
Delaware 17139 0.55
Des Moines 39400 1.25
Dickinson 17167 0.55
Dubuque 97162 3.09
Emmet 9428 0.30
Fayette 19680 0.63
Floyd 15778 0.50
Franklin 10150 0.32
Fremont 6927 0.22
Greene 8959 0.28
Grundy 12296 0.39
Guthrie 10652 0.34
Hamilton 15034 0.48
Hancock 10762 0.34
Hardin 17076 0.54
Harrison 14116 0.45
Henry 20056 0.64
Howard 9235 0.29
Humboldt 9568 0.30
Ida 6864 0.22
Iowa 16139 0.51
Jackson 19377 0.62
Jasper 36997 1.18
Jefferson 18108 0.58
Johnson 149703 4.76
Jones 20610 0.66
Keokuk 10144 0.32
Kossuth 14935 0.48
Lee 34239 1.09
Linn 224553 7.14
Louisa 11203 0.36
Lucas 8537 0.27
Lyon 11791 0.38
Madison 16005 0.51
Mahaska 22422 0.71
Marion 33107 1.05
Marshall 40051 1.27
Mills 15060 0.48
Mitchell 10544 0.34
Monona 8721 0.28
Monroe 7782 0.25
Montgomery 10119 0.32
Muscatine 42825 1.36
O'Brien 13777 0.44
Osceola 6024 0.19
Page 15253 0.49
Palo Alto 9045 0.29
Plymouth 25053 0.80
Pocahontas 6830 0.22
Polk 480962 15.30
Pottawattamie 93563 2.98
Poweshiek 18359 0.58
Ringgold 5029 0.16
Sac 9797 0.31
Scott 172691 5.49
Shelby 11584 0.37
Sioux 34784 1.11
Story 97335 3.10
Tama 17040 0.54
Taylor 6113 0.19
Union 12472 0.40
Van Buren 7155 0.23
Wapello 35043 1.12
Warren 50087 1.59
Washington 22236 0.71
Wayne 6488 0.21
Webster 36650 1.17
Winnebago 10582 0.34
Winneshiek 20140 0.64
Woodbury 102098 3.25
Worth 7456 0.24
Wright 12758 0.41