Population of Counties in Iowa (2017)

Name 2017 Population Growth Rate
Polk County474,0459.66%
Linn County221,6614.71%
Scott County172,4744.06%
Johnson County146,54711.62%
Black Hawk County132,9041.32%
Woodbury County102,7790.41%
Story County97,0908.32%
Dubuque County97,0033.28%
Pottawattamie County93,5820.23%
Dallas County84,51626.71%
Warren County49,6917.25%
Clinton County47,309-3.67%
Cerro Gordo County43,070-2.37%
Muscatine County42,9400.48%
Marshall County40,312-0.94%
Des Moines County39,739-1.29%
Webster County36,769-2.92%
Jasper County36,708-0.30%
Wapello County34,982-1.87%
Sioux County34,8983.45%
Lee County34,615-3.41%
Marion County33,189-0.13%
Boone County26,5320.97%
Benton County25,699-1.37%
Plymouth County25,2000.93%
Bremer County24,7982.11%
Washington County22,2812.70%
Mahaska County22,181-0.98%
Buchanan County20,9920.16%
Winneshiek County20,561-2.39%
Jones County20,439-1.12%
Carroll County20,437-1.88%
Buena Vista County20,3320.04%
Fayette County20,054-3.86%
Henry County19,773-1.69%
Jackson County19,472-1.82%
Poweshiek County18,533-1.98%
Cedar County18,454-0.19%
Jefferson County18,0907.52%
Clayton County17,590-2.72%
Delaware County17,327-2.49%
Tama County17,319-2.29%
Dickinson County17,2433.44%
Hardin County17,226-1.77%
Crawford County16,940-1.31%
Clay County16,333-1.81%
Iowa County16,311-0.17%
Floyd County15,873-2.62%
Madison County15,8480.72%
Page County15,391-3.44%
Kossuth County15,114-2.65%
Hamilton County15,076-3.61%
Mills County14,972-0.57%
Butler County14,791-0.77%
Harrison County14,149-5.21%
O'Brien County14,020-2.63%
Allamakee County13,884-3.25%
Cass County13,157-5.58%
Wright County12,779-3.17%
Appanoose County12,462-3.09%
Union County12,420-0.80%
Grundy County12,313-1.16%
Chickasaw County12,023-3.24%
Shelby County11,800-3.00%
Lyon County11,7541.62%
Cherokee County11,508-4.99%
Louisa County11,142-1.94%
Hancock County10,835-4.17%
Mitchell County10,763-0.40%
Winnebago County10,631-1.93%
Guthrie County10,625-2.94%
Montgomery County10,225-4.47%
Franklin County10,170-4.88%
Keokuk County10,119-3.60%
Sac County9,876-4.60%
Calhoun County9,846-3.20%
Emmet County9,658-6.07%
Humboldt County9,487-3.18%
Howard County9,332-2.40%
Clarke County9,309-0.03%
Palo Alto County9,047-3.69%
Greene County9,011-3.63%
Monona County8,898-3.63%
Davis County8,8601.03%
Lucas County8,647-2.74%
Decatur County8,141-3.33%
Monroe County7,870-1.45%
Worth County7,572-0.15%
Van Buren County7,271-3.81%
Adair County7,092-7.48%
Ida County6,985-1.16%
Fremont County6,950-6.46%
Pocahontas County6,886-5.37%
Wayne County6,4520.81%
Taylor County6,216-1.57%
Osceola County6,064-6.03%
Audubon County5,678-7.10%
Ringgold County5,068-1.05%
Adams County3,693-8.27%