• county
  • FIPS 19123
  • Largest town: Oskaloosa

Mahaska County, Iowa

Mahaska County had 22,034 residents in the Census Vintage 2024 estimate, on 570.9 square miles of land. It ranks 28th of 99 in Iowa by population and 46th by land area.

Population
22,034
#28 of 99 in Iowa · #1,720 in US
Area
570.9 sq mi
#46 of 99 in Iowa · #1,765 in US
Density
39 / sq mi
#28 of 99 in Iowa · #1,707 in US
Median household income
$71,332
#42 of 99 in Iowa · #907 in US

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

Mahaska County within Iowa. Pin: Des Moines.

Measure from here

Tools and pages that start from Mahaska County

Mahaska County population, land area and income

Mahaska County had 22,034 residents in the Census Vintage 2024 estimate, on 570.9 square miles of land. It ranks 28th of 99 in Iowa by population and 46th by land area. That works out to 38.6 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; Mahaska County is somewhat larger.

Its SAIPE 2023 median household income of $71,332 is above the national county median among 3,143 counties with an estimate.

National rank among 3,144

Population

22,034

3144th1st

1720th of 3,144 (US)

Land area

571 sq mi

3144th1st

1765th of 3,144 (US)

Density

38.6 / sq mi

3144th1st

1707th of 3,144 (US)

Median household income

$71,332

3143rd1st

907th of 3,143 (US)

Rank within Iowa (99)

Population

22,034

99th1st

28th of 99 (IA)

Land area

571 sq mi

99th1st

46th of 99 (IA)

Density

38.6 / sq mi

99th1st

28th of 99 (IA)

Median household income

$71,332

99th1st

42nd of 99 (IA)

How Mahaska County's population changed since 2020

Mahaska County lost 128 residents between the July 2020 and July 2024 estimates, a drop of 0.6%. That ranks 48th 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, Mahaska County recorded 991 births and 1,153 deaths, a natural change of -162. Net international migration added +190 and net domestic migration, people moving to or from other US counties, came to -179. The largest single component was international migration, which added 190 people.

22.2k202022.0k202122.0k202222.0k202322.0k2024
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
991
Deaths
1,153
Net international migration
+190
Net domestic migration
-179
Change, July 2023 to July 2024
+67

Where Mahaska County is

The Census internal point of Mahaska County is at 41.330800, -92.636400. 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 Mahaska 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: Mahaska County internal point. Dark pin: Des Moines.

Internal point

Decimal
41.330800, -92.636400
DMS
41°19'50.88"N 92°38'11.04"W
UTM
15N 530425.9E 4575543.8N
Geohash
9zq5hh01r
Plus code
86H989J7+8C

Towns in Mahaska County

3 incorporated places of 1,000+ people have residents in Mahaska County, 12,825 people together, or 58% of the county. Each figure counts only the part of the town inside Mahaska County; towns marked "part" extend into another county. The largest is Oskaloosa with 11,575.

  1. 01Oskaloosa11,575
  2. 02New Sharon1,249
  3. 03Pella (part)1
Census Vintage 2024 subcounty estimates, county parts of incorporated places (SUMLEV 157).

Counties bordering Mahaska County

The Census 2024 county adjacency file lists 6 neighbors for Mahaska County. The most populous is Jasper County, IA, with 38,107 residents. Distances run between Census internal points in a straight line.

Distance to Des Moines and the nearest big city

Des Moines is 53.2 miles WNW of Mahaska County's internal point in a straight line. The nearest place of 100,000 or more is Des Moines, IA (population 213,096), 53.1 miles away. The nearest place of 10,000 or more is Oskaloosa, IA (population 11,575), 2.7 miles away.

Mahaska County FIPS code

The FIPS code of Mahaska County is 19123: state code 19 for Iowa plus county code 123. Use it as text, with the leading zero, when joining Census, BLS, or CDC county tables. SAIPE lists its 2023 median household income as $71,332.

Questions people ask

What is the population of Mahaska County, Iowa?

The Census Vintage 2024 estimate for July 1, 2024 is 22,034. That is down 128 people (0.6%) from the July 2020 estimate of 22,162.

What is the FIPS code of Mahaska County?

19123. The first two digits (19) are Iowa; the last three (123) identify the county.

What is the largest town in Mahaska County?

Oskaloosa, with 11,575 residents inside Mahaska County in 2024.

Which counties border Mahaska County?

6 county-equivalents border it in the Census 2024 adjacency file: Jasper County, IA; Wapello County, IA; Marion County, IA; Poweshiek County, IA; Keokuk County, IA; Monroe 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.