Iowa

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Iowa counties by population

Number of counties: 99
Population: 3,179,090
Largest county: Polk County
Table of counties in Iowa sorted by population from largest to smallest.
CountyPopulation
Polk County488,871
Linn County228,567
Scott County174,170
Johnson County151,833
Black Hawk County131,396
Woodbury County105,102
Dubuque County98,687
Story County98,106
Dallas County96,604
Pottawattamie County93,571
Warren County51,862
Clinton County46,589
Cerro Gordo County43,185
Muscatine County43,145
Marshall County40,137
Des Moines County39,069
Jasper County37,686
Webster County37,114
Sioux County35,647
Wapello County35,343
Lee County33,724
Marion County33,381
Boone County26,721
Benton County25,654
Plymouth County25,543
Bremer County24,863
Washington County22,525
Mahaska County22,132
Carroll County20,756
Buena Vista County20,723
Jones County20,680
Buchanan County20,598
Henry County20,488
Winneshiek County20,100
Fayette County19,582
Jackson County19,499
Poweshiek County18,628
Cedar County18,494
Dickinson County17,536
Delaware County17,508
Clayton County17,173
Tama County17,079
Hardin County16,997
Iowa County16,596
Crawford County16,555
Madison County16,414
Clay County16,410
Jefferson County15,846
Floyd County15,672
Page County15,250
Hamilton County15,073
Kossuth County14,823
Mills County14,658
Harrison County14,589
Butler County14,421
O'Brien County14,139
Allamakee County14,068
Cass County13,158
Wright County12,978
Grundy County12,336
Appanoose County12,310
Union County12,193
Chickasaw County12,021
Lyon County11,953
Shelby County11,750
Cherokee County11,606
Louisa County10,891
Hancock County10,837
Winnebago County10,743
Guthrie County10,599
Mitchell County10,526
Montgomery County10,327
Franklin County10,056
Keokuk County10,050
Calhoun County9,962
Sac County9,829
Clarke County9,736
Humboldt County9,622
Howard County9,456
Emmet County9,433
Davis County9,066
Palo Alto County8,996
Greene County8,831
Monona County8,732
Lucas County8,650
Decatur County7,718
Monroe County7,589
Worth County7,450
Adair County7,439
Van Buren County7,196
Pocahontas County7,091
Ida County6,979
Fremont County6,702
Wayne County6,504
Osceola County6,168
Taylor County5,932
Audubon County5,657
Ringgold County4,739
Adams County3,697

What is the largest county in Iowa?

Polk County is the largest county in Iowa with a population of 488,871.

TOP-5 counties by population in Iowa:
  • Polk County
  • Linn County
  • Scott County
  • Johnson County
  • Black Hawk County