COUNTY · IA

Mahaska County, Iowa

Mahaska County is a county in Iowa with FIPS code 19123 and an estimated population of 21,874 (Census 2023), 28th largest of 99 in the state.

County facts

Name
Mahaska County
State
Iowa
Type
county
FIPS code
19123
State FIPS
19
Population (2023)
21,874
Change since 2020
-1.3%
State rank
28 of 99

Population is the Census Bureau’s Vintage 2023 estimate.

Other counties in Iowa

Questions

What is the FIPS code for Mahaska County?

Mahaska County, Iowa has the five-digit FIPS code 19123: 19 for the state and 123 for the county.

What state is Mahaska County in?

Mahaska County is in Iowa.

How do I know if an address is in this county?

Use the address lookup. ZIP codes and city names can cross county lines, so an address is the reliable check.

Sources: U.S. Census Bureau geographic reference files; Census Bureau Population Estimates, Vintage 2023. Last reviewed 2026-10-27.