Mahaska County Demographics

A map of Mahaska County's Population by Race

Race	2024 Pop	2020 Pop	2024 %	2020 %
White	20,161	20,259	91.6%	91.3%
Multiracial	744	727	3.4%	3.3%
Hispanic	550	480	2.5%	2.2%
Black	247	384	1.1%	1.7%
Asian	229	250	1.0%	1.1%
Native American/Other	90	90	0.4%	0.4%

Mahaska County, Iowa has an estimated population of 22,021, a less than 1% change from the 22,190 recorded in the 2020 Census. The population is 91.6% White, 3.4% Multiracial, 2.5% Hispanic, 1.1% Black, 1.0% Asian, and 0.4% Native American/Other. This demographic dot map shows the population of Mahaska County, with one dot drawn for each person counted by the Census, color-coded by race.

Mahaska is about as racially diverse as it was in the 2020 Census. It is considerably less diverse than Iowa overall. Demographers use a diversity index to measure the probability that two randomly selected individuals belong to different racial or ethnic groups. In Mahaska County, that probability was 16.4% in 2020 and 16.0% in the most recent ACS estimates.

Mahaska County is ranked the 28th most populous county in Iowa, out of 99 counties. Mahaska County was ranked the 28th most populous county in the 2020 Census.

Mahaska County's White Population

20,161 residents of Mahaska County, or 91.6% of the population, identify as White. The share of White residents in Mahaska County is higher than in Iowa overall, where 82.3% of the population is White. Mahaska County ranks 55th statewide in terms of White residents as a share of the population, out of 99 counties.

Since the 2020 Census, Mahaska County's White population has remained roughly the same. White residents' share of Mahaska County's population has remained roughly unchanged at 91.6%.

Mahaska County is more White than neighboring Poweshiek County (89.8% White), and Wapello County (75.6% White). Mahaska County is less White than neighboring Monroe County (94.8% White), Marion County (93.3% White), and Keokuk County (94.6% White).

Mahaska County's Black Population

247 residents of Mahaska County, or 1.1% of the population, identify as Black. The share of Black residents in Mahaska County is slightly lower than in Iowa overall, where 3.8% of the population is Black. Mahaska County ranks 28th statewide in terms of Black residents as a share of the population, out of 99 counties.

Since the 2020 Census, Mahaska County's Black population has declined by an estimated 35.7%. Black residents' share of Mahaska County's population has decreased from 1.7% to 1.1%.

Mahaska County is more Black than neighboring Poweshiek County (0.9% Black), Marion County (0.4% Black), and Keokuk County (0.3% Black). Mahaska County is less Black than neighboring Monroe County (1.2% Black), and Wapello County (3% Black).

Mahaska County's Asian Population

229 residents of Mahaska County, or 1.0% of the population, identify as Asian. The share of Asian residents in Mahaska County is comparable to the share in Iowa overall, where 2.5% of the population is Asian. Mahaska County ranks 21st statewide in terms of Asian residents as a share of the population, out of 99 counties.

Since the 2020 Census, Mahaska County's Asian population has declined by an estimated 8.4%. Asian residents' share of Mahaska County's population has remained roughly unchanged at 1.0%.

Mahaska County is more Asian than neighboring Monroe County (0.5% Asian), and Keokuk County (0.2% Asian). Mahaska County is less Asian than neighboring Poweshiek County (2% Asian), Wapello County (1.6% Asian), and Marion County (1.4% Asian).

Mahaska County's Hispanic Population

550 residents of Mahaska County, or 2.5% of the population, identify as Hispanic. The share of Hispanic residents in Mahaska County is slightly lower than in Iowa overall, where 7.3% of the population is Hispanic. Mahaska County ranks 78th statewide in terms of Hispanic residents as a share of the population, out of 99 counties.

Since the 2020 Census, Mahaska County's Hispanic population has grown by an estimated 14.6%. Hispanic residents' share of Mahaska County's population has remained roughly unchanged at 2.5%.

Mahaska County is more Hispanic than neighboring Monroe County (2.1% Hispanic), Marion County (2.3% Hispanic), and Keokuk County (2.3% Hispanic). Mahaska County is less Hispanic than neighboring Poweshiek County (3.5% Hispanic), and Wapello County (13.4% Hispanic).

Mahaska County's Native American/Other Population

90 residents of Mahaska County, or 0.4% of the population, identify as American Indian/Alaska Native/Native Hawaiian/Pacific Islander/Other. The share of Native American/Other residents in Mahaska County is comparable to the share in Iowa overall, where 0.6% of the population is Native American/Other. Mahaska County ranks 57th statewide in terms of Native American/Other residents as a share of the population, out of 99 counties.

Since the 2020 Census, Mahaska County's Native American/Other population has remained roughly the same. Native American/Other residents' share of Mahaska County's population has remained roughly unchanged at 0.4%.

Mahaska County is more Native American/Other than neighboring Marion County (0.3% Native American/Other), and Keokuk County (0.3% Native American/Other). Mahaska County is less Native American/Other than neighboring Wapello County (2.6% Native American/Other).

Mahaska County's Multiracial Population

744 residents of Mahaska County, or 3.4% of the population, identify as Multiracial. The share of Multiracial residents in Mahaska County is comparable to the share in Iowa overall, where 3.5% of the population is Multiracial. Mahaska County ranks 18th statewide in terms of Multiracial residents as a share of the population, out of 99 counties.

Since the 2020 Census, Mahaska County's Multiracial population has grown by an estimated 2.3%. Multiracial residents' share of Mahaska County's population has remained roughly unchanged at 3.4%.

Mahaska County is more Multiracial than neighboring Poweshiek County (3.3% Multiracial), Monroe County (1.1% Multiracial), Marion County (2.3% Multiracial), and Keokuk County (2.3% Multiracial). Mahaska County is less Multiracial than neighboring Wapello County (3.7% Multiracial).

Sources: Most recent population estimates are from the 2020-2024 American Community Survey 5-Year Estimates. 2020 population counts and map data are from 2020 Census State Redistricting Data. Geographic data are from Census TIGER/Line Shapefiles.