• county
  • FIPS 19183
  • Largest town: Washington

Washington County, Iowa

Washington County had 22,631 residents in the Census Vintage 2024 estimate, on 568.8 square miles of land. It ranks 27th of 99 in Iowa by population and 54th by land area.

Population
22,631
#27 of 99 in Iowa · #1,694 in US
Area
568.8 sq mi
#54 of 99 in Iowa · #1,793 in US
Density
40 / sq mi
#27 of 99 in Iowa · #1,678 in US
Median household income
$75,136
#21 of 99 in Iowa · #662 in US

Census Vintage 2024 estimates · SAIPE 2023 income · 2024 Gazetteer land area

Washington County within Iowa. Pin: Des Moines.

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Tools and pages that start from Washington County

Washington County population, land area and income

Washington County had 22,631 residents in the Census Vintage 2024 estimate, on 568.8 square miles of land. It ranks 27th of 99 in Iowa by population and 54th by land area. That works out to 39.8 people per square mile, below the US average of 96.3, and below the national county median.

The median county-equivalent in Iowa has 15,008 residents; Washington County is somewhat larger.

Its SAIPE 2023 median household income of $75,136 is in the top quarter among 3,143 counties with an estimate.

National rank among 3,144

Population

22,631

3144th1st

1694th of 3,144 (US)

Land area

569 sq mi

3144th1st

1793rd of 3,144 (US)

Density

39.8 / sq mi

3144th1st

1678th of 3,144 (US)

Median household income

$75,136

3143rd1st

662nd of 3,143 (US)

Rank within Iowa (99)

Population

22,631

99th1st

27th of 99 (IA)

Land area

569 sq mi

99th1st

54th of 99 (IA)

Density

39.8 / sq mi

99th1st

27th of 99 (IA)

Median household income

$75,136

99th1st

21st of 99 (IA)

How Washington County's population changed since 2020

Washington County gained 90 residents between the July 2020 and July 2024 estimates, a rise of 0.4%. That ranks 37th of 99 in Iowa for growth. The median Iowa county changed by -0.6%, and the state as a whole by +1.6%.

Since the April 2020 estimates base, Washington County recorded 1,170 births and 1,126 deaths, a natural change of +44. Net international migration added +150 and net domestic migration, people moving to or from other US counties, came to -125. The largest single component was international migration, which added 150 people.

22.5k202022.5k202122.5k202222.6k202322.6k2024
Census Vintage 2024 county estimates for July 1 of each year. The axis starts above zero so year-to-year changes are visible.

Components of change, April 2020 to July 2024

Births
1,170
Deaths
1,126
Net international migration
+150
Net domestic migration
-125
Change, July 2023 to July 2024
+77

Where Washington County is

The Census internal point of Washington County is at 41.329400, -91.725100. It sits in UTM zone 15N. The map shades Iowa's 99 county-equivalents by population change from 2020 to 2024, darker for faster growth, with Washington County outlined. Dots are towns of 1,000+ people with residents in it.

Monroe County: -2.9%Worth County: -1.7%Buena Vista County: +0.0%Jasper County: +0.8%Van Buren County: -0.0%Hardin County: -2.2%Ida County: -3.1%Marshall County: +0.8%Fayette County: -1.5%Ringgold County: -0.8%Wapello County: +1.0%Webster County: -0.2%Adams County: -2.8%Buchanan County: +0.6%Cerro Gordo County: -1.2%Lucas County: +1.6%Emmet County: -1.9%Floyd County: -3.8%Crawford County: -0.7%Linn County: +0.6%Montgomery County: -2.6%Polk County: +4.7%Cherokee County: +0.0%Bremer County: +1.3%Grundy County: +0.5%Adair County: -0.8%Cedar County: -1.4%Story County: +3.9%Mahaska County: -0.6%Davis County: +0.9%Clay County: +0.8%Johnson County: +4.6%Greene County: -1.0%Palo Alto County: -2.0%Benton County: +1.0%Cass County: -0.7%Wright County: -1.5%Audubon County: -2.1%Henry County: -5.3%Boone County: +0.1%Appanoose County: -1.4%Washington County: +0.4%Chickasaw County: -2.2%Poweshiek County: -0.9%Osceola County: -2.6%Wayne County: +1.8%Mitchell County: +0.4%Jefferson County: +0.5%Union County: -1.4%Butler County: -1.2%Hancock County: -1.3%Marion County: +1.9%Delaware County: +0.9%Humboldt County: +0.2%Sioux County: +1.8%Des Moines County: -1.1%O'Brien County: +0.8%Clayton County: -0.6%Black Hawk County: +1.0%Winnebago County: -2.6%Harrison County: +0.4%Decatur County: -1.0%Pocahontas County: -0.9%Lyon County: +3.8%Iowa County: -1.4%Franklin County: +0.3%Dickinson County: +2.2%Madison County: +3.2%Allamakee County: +0.8%Jones County: +2.2%Carroll County: -1.6%Kossuth County: -2.6%Hamilton County: -1.0%Howard County: -1.4%Page County: -1.1%Guthrie County: +1.5%Tama County: -1.8%Monona County: -3.6%Clarke County: -2.1%Lee County: -3.4%Mills County: +2.1%Sac County: -2.7%Scott County: +0.6%Keokuk County: -1.6%Jackson County: -0.3%Warren County: +7.1%Calhoun County: -1.9%Shelby County: +0.8%Fremont County: -1.1%Dubuque County: -0.1%Louisa County: -1.8%Taylor County: -0.6%Woodbury County: +1.2%Clinton County: -0.9%Winneshiek County: -1.6%Pottawattamie County: -0.1%Plymouth County: +0.5%Muscatine County: -2.4%Dallas County: +14.7%
Change 2020 to 2024
  1. < -1.9%
  2. < -1.0%
  3. < +0.0%
  4. < +0.9%
  5. ≥ +0.9%
no data

Orange pin: Washington County internal point. Dark pin: Des Moines.

Internal point

Decimal
41.329400, -91.725100
DMS
41°19'45.84"N 91°43'30.36"W
UTM
15N 606686.6E 4576108.6N
Geohash
9zqg0ezc4
Plus code
86HC87HF+QX

Towns in Washington County

4 incorporated places of 1,000+ people have residents in Washington County, 12,637 people together, or 56% of the county. Each figure counts only the part of the town inside Washington County; towns marked "part" extend into another county. The largest is Washington with 7,281.

  1. 01Washington7,281
  2. 02Kalona2,762
  3. 03Wellman1,531
  4. 04Riverside1,063
Census Vintage 2024 subcounty estimates, county parts of incorporated places (SUMLEV 157).

Counties bordering Washington County

The Census 2024 county adjacency file lists 6 neighbors for Washington County. The most populous is Johnson County, IA, with 160,080 residents. Distances run between Census internal points in a straight line.

Distance to Des Moines and the nearest big city

Des Moines is 99.0 miles W of Washington County's internal point in a straight line. The nearest place of 100,000 or more is Cedar Rapids, IA (population 137,904), 43.9 miles away. The nearest place of 10,000 or more is Iowa City, IA (population 76,710), 24.7 miles away.

Washington County FIPS code

The FIPS code of Washington County is 19183: state code 19 for Iowa plus county code 183. Use it as text, with the leading zero, when joining Census, BLS, or CDC county tables. SAIPE lists its 2023 median household income as $75,136.

Questions people ask

What is the population of Washington County, Iowa?

The Census Vintage 2024 estimate for July 1, 2024 is 22,631. That is up 90 people (0.4%) from the July 2020 estimate of 22,541.

What is the FIPS code of Washington County?

19183. The first two digits (19) are Iowa; the last three (183) identify the county.

What is the largest town in Washington County?

Washington, with 7,281 residents inside Washington County in 2024.

Which counties border Washington County?

6 county-equivalents border it in the Census 2024 adjacency file: Johnson County, IA; Henry County, IA; Iowa County, IA; Jefferson County, IA; Louisa County, IA; Keokuk County, IA.

Sources and data as of

Data as of: Census Vintage 2024 population estimates, 2024 Gazetteer land area and internal points, SAIPE 2023 median household income.

  1. 01Census Vintage 2024 county population estimates
  2. 02Census 2024 Gazetteer, counties
  3. 03Census SAIPE 2023 state and county estimates
  4. 04Census Vintage 2024 subcounty population estimates
  5. 05Census 2024 county adjacency file
  6. 06Census 2024 cartographic boundary file, counties (1:5,000,000)

How every number is computed: methodology. Spotted a wrong figure? Report an error.