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zipcodes.pro — STATE/IA/COUNTY/MAHASKA

Mahaska County, IA ZIP codes

There are 9 ZIP codes in Mahaska County, IA, in 9 towns, from 50027 to 52595. The largest are 52577 (Oskaloosa), 50207 (New Sharon) and 52561 (Fremont). 1 more crosses into it from a neighbouring county: 50219.

The county seat is Oskaloosa.

ZIP codes
9
Partly in it
1 more
Towns
9
County seat
Oskaloosa
County FIPS
19123
State
Iowa
Population
22,021
Median household income
$70,940
Land area
571 sq mi
Area code
641
Metro area
Oskaloosa

Mahaska County ZIP codes by town

Oskaloosa (county seat)
52577

Each ZIP code is listed under the county most of its land lies in and the town the Postal Service names it for; a ZIP code's own page shows exactly how it is split.

ZIP codes partly in Mahaska County

This ZIP code lies mostly in a neighbouring county but covers a twentieth or more of Mahaska County.

Map of Mahaska County ZIP codes

500275014350207525345254352561525775258652595

The ZIP codes of Mahaska County, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.

Mahaska County in numbers

About 22,021 people live in Mahaska County, in 8,743 households, the 28th most populous of Iowa's 99 counties. The median household income is $70,940 a year, 5% below the Iowa median of $75,059 (US: $80,734). The median owner-occupied home is valued at $157,800 (24% below the Iowa median), and median gross rent is $793 a month. The median age is 39.0; 24.1% of adults 25 and over hold a bachelor's degree or higher (31.4% across Iowa); the average commute takes 18 minutes.

Population22,021Mahaska22,021
Households8,743Mahaska8,743
Median age39.0Mahaska39.0Iowa38.6US 38.9
Median household income$70,940Mahaska$70,940Iowa$75,059US $80,734
Median home value$157,800Mahaska$157,800Iowa$208,000US $332,700
Median gross rent$793Mahaska$793Iowa$972US $1,413
Bachelor's degree or higher24.1%Mahaska24.1%Iowa31.4%US 35.7%
Mean commute18.0 minMahaska18.0 minIowa19.8 minUS 26.4 min
Population density39 / sq miMahaska39 / sq mi

U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates. Survey estimates carry margins of error, wider for small places. Sources and methods.

Largest towns in Mahaska County

Largest towns in Mahaska County
TownZIP codesPopulation
Oskaloosa 1 11,504
New Sharon 1 1,180
Fremont 1 924
University Park 1 645
Cedar 1 541
Beacon 1 425
Rose Hill 1 300
Leighton 1 150
Barnes City 1 117

Population of the census place of that name where there is one, otherwise of the ZIP codes the Postal Service addresses by it. A town's ZIP codes can reach past the county line.

Neighbouring counties

Counties that share a ZIP code with Mahaska County.

Not sure you are in Mahaska County? What county am I in? answers from your location, near a county line included.

Every ZIP code in Mahaska County, with figures

ZIP codes in Mahaska County
ZIP City Type Population Median income Median home
50027 Barnes City , IA Standard 148 $52,976 $85,000
50143 Leighton , IA Standard 538 $86,023 $314,600
50207 New Sharon , IA Standard 2,325 $76,053 $156,300
52534 Beacon , IA Standard 321 $57,986 $75,700
52543 Cedar , IA Standard 541 $83,511 —
52561 Fremont , IA Standard 1,112 $76,058 $123,200
52577 Oskaloosa , IA Standard 14,585 $66,084 $163,300
52586 Rose Hill , IA Standard 600 $53,125 $104,500
52595 University Park , IA Standard 545 $66,667 $104,800

Cite this page

zipcodes.pro. “Mahaska County ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/ia/county/mahaska

Underlying data is public domain or openly licensed — sources, vintages and licences.