County research and study

Iowa county reference

99 counties and county equivalents in Iowa. Search names or FIPS codes, compare Census geography and keep the original sources with your work.

• Adair County

  Iowa · FIPS 19001

  7,403 residents · 2025 estimate

• Adams County

  Iowa · FIPS 19003

  3,617 residents · 2025 estimate

• Allamakee County

  Iowa · FIPS 19005

  14,238 residents · 2025 estimate

• Appanoose County

  Iowa · FIPS 19007

  12,077 residents · 2025 estimate

• Audubon County

  Iowa · FIPS 19009

  5,509 residents · 2025 estimate

• Benton County

  Iowa · FIPS 19011

  26,004 residents · 2025 estimate

• Black Hawk County

  Iowa · FIPS 19013

  131,532 residents · 2025 estimate

• Boone County

  Iowa · FIPS 19015

  26,799 residents · 2025 estimate

• Bremer County

  Iowa · FIPS 19017

  25,296 residents · 2025 estimate

• Buchanan County

  Iowa · FIPS 19019

  20,883 residents · 2025 estimate

• Buena Vista County

  Iowa · FIPS 19021

  20,449 residents · 2025 estimate

• Butler County

  Iowa · FIPS 19023

  14,049 residents · 2025 estimate

• Calhoun County

  Iowa · FIPS 19025

  9,562 residents · 2025 estimate

• Carroll County

  Iowa · FIPS 19027

  20,303 residents · 2025 estimate

• Cass County

  Iowa · FIPS 19029

  12,960 residents · 2025 estimate

• Cedar County

  Iowa · FIPS 19031

  18,359 residents · 2025 estimate

• Cerro Gordo County

  Iowa · FIPS 19033

  42,372 residents · 2025 estimate

• Cherokee County

  Iowa · FIPS 19035

  11,369 residents · 2025 estimate

• Chickasaw County

  Iowa · FIPS 19037

  11,663 residents · 2025 estimate

• Clarke County

  Iowa · FIPS 19039

  9,574 residents · 2025 estimate

• Clay County

  Iowa · FIPS 19041

  16,202 residents · 2025 estimate

• Clayton County

  Iowa · FIPS 19043

  16,845 residents · 2025 estimate

• Clinton County

  Iowa · FIPS 19045

  46,002 residents · 2025 estimate

• Crawford County

  Iowa · FIPS 19047

  16,237 residents · 2025 estimate

• Dallas County

  Iowa · FIPS 19049

  118,457 residents · 2025 estimate

• Davis County

  Iowa · FIPS 19051

  9,230 residents · 2025 estimate

• Decatur County

  Iowa · FIPS 19053

  7,655 residents · 2025 estimate

• Delaware County

  Iowa · FIPS 19055

  17,674 residents · 2025 estimate

• Des Moines County

  Iowa · FIPS 19057

  38,077 residents · 2025 estimate

• Dickinson County

  Iowa · FIPS 19059

  18,077 residents · 2025 estimate

• Dubuque County

  Iowa · FIPS 19061

  99,381 residents · 2025 estimate

• Emmet County

  Iowa · FIPS 19063

  9,107 residents · 2025 estimate

• Fayette County

  Iowa · FIPS 19065

  19,047 residents · 2025 estimate

• Floyd County

  Iowa · FIPS 19067

  14,901 residents · 2025 estimate

• Franklin County

  Iowa · FIPS 19069

  9,868 residents · 2025 estimate

• Fremont County

  Iowa · FIPS 19071

  6,522 residents · 2025 estimate

• Greene County

  Iowa · FIPS 19073

  8,658 residents · 2025 estimate

• Grundy County

  Iowa · FIPS 19075

  12,361 residents · 2025 estimate

• Guthrie County

  Iowa · FIPS 19077

  10,782 residents · 2025 estimate

• Hamilton County

  Iowa · FIPS 19079

  14,944 residents · 2025 estimate

• Hancock County

  Iowa · FIPS 19081

  10,528 residents · 2025 estimate

• Hardin County

  Iowa · FIPS 19083

  16,455 residents · 2025 estimate

• Harrison County

  Iowa · FIPS 19085

  14,623 residents · 2025 estimate

• Henry County

  Iowa · FIPS 19087

  19,349 residents · 2025 estimate

• Howard County

  Iowa · FIPS 19089

  9,415 residents · 2025 estimate

• Humboldt County

  Iowa · FIPS 19091

  9,409 residents · 2025 estimate

• Ida County

  Iowa · FIPS 19093

  6,777 residents · 2025 estimate

• Iowa County

  Iowa · FIPS 19095

  16,504 residents · 2025 estimate

• Jackson County

  Iowa · FIPS 19097

  19,288 residents · 2025 estimate

• Jasper County

  Iowa · FIPS 19099

  38,153 residents · 2025 estimate

• Jefferson County

  Iowa · FIPS 19101

  15,291 residents · 2025 estimate

• Johnson County

  Iowa · FIPS 19103

  160,044 residents · 2025 estimate

• Jones County

  Iowa · FIPS 19105

  21,253 residents · 2025 estimate

• Keokuk County

  Iowa · FIPS 19107

  9,797 residents · 2025 estimate

• Kossuth County

  Iowa · FIPS 19109

  14,322 residents · 2025 estimate

• Lee County

  Iowa · FIPS 19111

  32,306 residents · 2025 estimate

• Linn County

  Iowa · FIPS 19113

  232,028 residents · 2025 estimate

• Louisa County

  Iowa · FIPS 19115

  10,416 residents · 2025 estimate

• Lucas County

  Iowa · FIPS 19117

  8,847 residents · 2025 estimate

• Lyon County

  Iowa · FIPS 19119

  12,354 residents · 2025 estimate

• Madison County

  Iowa · FIPS 19121

  17,270 residents · 2025 estimate

• Mahaska County

  Iowa · FIPS 19123

  21,880 residents · 2025 estimate

• Marion County

  Iowa · FIPS 19125

  34,192 residents · 2025 estimate

• Marshall County

  Iowa · FIPS 19127

  39,890 residents · 2025 estimate

• Mills County

  Iowa · FIPS 19129

  14,793 residents · 2025 estimate

• Mitchell County

  Iowa · FIPS 19131

  10,650 residents · 2025 estimate

• Monona County

  Iowa · FIPS 19133

  8,539 residents · 2025 estimate

• Monroe County

  Iowa · FIPS 19135

  7,406 residents · 2025 estimate

• Montgomery County

  Iowa · FIPS 19137

  10,002 residents · 2025 estimate

• Muscatine County

  Iowa · FIPS 19139

  41,853 residents · 2025 estimate

• O'Brien County

  Iowa · FIPS 19141

  14,220 residents · 2025 estimate

• Osceola County

  Iowa · FIPS 19143

  5,980 residents · 2025 estimate

• Page County

  Iowa · FIPS 19145

  14,856 residents · 2025 estimate

• Palo Alto County

  Iowa · FIPS 19147

  8,899 residents · 2025 estimate

• Plymouth County

  Iowa · FIPS 19149

  25,697 residents · 2025 estimate

• Pocahontas County

  Iowa · FIPS 19151

  6,819 residents · 2025 estimate

• Polk County

  Iowa · FIPS 19153

  516,546 residents · 2025 estimate

• Pottawattamie County

  Iowa · FIPS 19155

  92,996 residents · 2025 estimate

• Poweshiek County

  Iowa · FIPS 19157

  18,368 residents · 2025 estimate

• Ringgold County

  Iowa · FIPS 19159

  4,642 residents · 2025 estimate

• Sac County

  Iowa · FIPS 19161

  9,525 residents · 2025 estimate

• Scott County

  Iowa · FIPS 19163

  175,259 residents · 2025 estimate

• Shelby County

  Iowa · FIPS 19165

  11,689 residents · 2025 estimate

• Sioux County

  Iowa · FIPS 19167

  36,774 residents · 2025 estimate

• Story County

  Iowa · FIPS 19169

  101,291 residents · 2025 estimate

• Tama County

  Iowa · FIPS 19171

  16,796 residents · 2025 estimate

• Taylor County

  Iowa · FIPS 19173

  5,835 residents · 2025 estimate

• Union County

  Iowa · FIPS 19175

  11,829 residents · 2025 estimate

• Van Buren County

  Iowa · FIPS 19177

  7,131 residents · 2025 estimate

• Wapello County

  Iowa · FIPS 19179

  35,210 residents · 2025 estimate

• Warren County

  Iowa · FIPS 19181

  57,331 residents · 2025 estimate

• Washington County

  Iowa · FIPS 19183

  22,667 residents · 2025 estimate

• Wayne County

  Iowa · FIPS 19185

  6,738 residents · 2025 estimate

• Webster County

  Iowa · FIPS 19187

  36,838 residents · 2025 estimate

• Winnebago County

  Iowa · FIPS 19189

  10,251 residents · 2025 estimate

• Winneshiek County

  Iowa · FIPS 19191

  19,733 residents · 2025 estimate

• Woodbury County

  Iowa · FIPS 19193

  106,649 residents · 2025 estimate

• Worth County

  Iowa · FIPS 19195

  7,338 residents · 2025 estimate

• Wright County

  Iowa · FIPS 19197

  12,801 residents · 2025 estimate

Use the county data

Use a county profile as a source-reading exercise or the geographic context for your own research. Keep the county FIPS identifier with your notes so that similarly named places in different states are not mixed.

The figures describe the county; they are not an evaluation of schools or an estimate of educational outcomes.

Geography: 2025 U.S. Census Gazetteer. Population: Vintage 2025 estimates, July 1, 2025. County equivalents include parishes, boroughs, independent cities and planning regions. Puerto Rico population is not supplied by this population file.