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Population per Square Mile in Iowa, by County

Population per Square Mile for every county in Iowa, ranked. The highest is Polk County at 878.6 and the lowest is Adams County at 8.6.

Iowa: 57.5 · United States: n/a · median county in Iowa: 26.4

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#County Population per Square Mile
1Polk County878.6
2Scott County381.2
3Linn County320.8
4Johnson County255.5
5Black Hawk County231.6
6Dallas County183.5
7Story County175.5
8Dubuque County162.8
9Woodbury County121.7
10Pottawattamie County98.2
11Muscatine County97.3
12Warren County95.5
13Des Moines County92.5
14Wapello County81.9
15Cerro Gordo County75.0
16Marshall County70.1
17Clinton County66.6
18Lee County63.6
19Marion County60.7
20Bremer County57.9
21Jasper County52.0
22Webster County51.5
23Dickinson County47.3
24Sioux County47.2
25Boone County46.7
26Henry County46.1
27Washington County39.7
28Mahaska County38.6
29Jones County36.3
30Buchanan County36.2
31Carroll County36.2
32Buena Vista County36.1
33Jefferson County36.1
34Benton County35.9
35Mills County33.3
36Cedar County31.7
37Poweshiek County31.7
38Floyd County30.6
39Jackson County30.5
40Delaware County30.4
41Madison County30.2
42Plymouth County29.8
43Hardin County29.2
44Clay County29.0
45Winneshiek County28.8
46Page County28.3
47Union County28.3
48Iowa County28.1
49Louisa County26.6
50Fayette County26.4
51Winnebago County26.4
52Hamilton County25.8
53Grundy County24.7
54O'Brien County24.7
55Butler County24.6
56Appanoose County24.5
57Montgomery County24.1
58Chickasaw County23.4
59Emmet County23.4
60Tama County23.4
61Cass County23.2
62Crawford County22.8
63Mitchell County22.5
64Clarke County22.4
65Allamakee County22.1
66Humboldt County22.1
67Wright County22.0
68Clayton County21.9
69Harrison County21.0
70Lyon County20.7
71Lucas County20.2
72Cherokee County20.1
73Howard County20.0
74Shelby County19.9
75Hancock County18.7
76Worth County18.4
77Davis County18.2
78Guthrie County18.1
79Monroe County17.3
80Calhoun County17.2
81Franklin County17.1
82Keokuk County17.1
83Sac County16.8
84Ida County16.0
85Palo Alto County15.7
86Greene County15.3
87Osceola County15.3
88Kossuth County14.9
89Van Buren County14.9
90Decatur County14.6
91Adair County13.1
92Fremont County12.7
93Audubon County12.6
94Wayne County12.4
95Monona County12.3
96Pocahontas County12.2
97Taylor County11.0
98Ringgold County8.7
99Adams County8.6

People divided by land area. Water is excluded, so lake and coastal counties are not unfairly diluted.

Source: ACS 2020-2024 5-Year Estimates, 2024.

Iowa ranks 38th of 52 states for population per square mile.

Population per Square Mile in other states

Other statistics for Iowa by county