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zipcodes.pro — STATE/IA/COUNTY/CASS

Cass County, IA ZIP codes

There are 8 ZIP codes in Cass County, IA, in 8 towns, from 50020 to 51552. The largest are 50022 (Atlantic), 51535 (Griswold) and 50020 (Anita).

The county seat is Atlantic.

ZIP codes
8
Towns
8
County seat
Atlantic
County FIPS
19029
State
Iowa
Population
13,096
Median household income
$63,013
Land area
564 sq mi

Cass County ZIP codes by town

Atlantic (county seat)
50022

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.

Map of Cass County ZIP codes

5002050022502745084350853515355154451552

The ZIP codes of Cass 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.

Cass County in numbers

About 13,096 people live in Cass County, in 5,844 households, the 58th most populous of Iowa's 99 counties. The median household income is $63,013 a year, 16% below the Iowa median of $75,059 (US: $80,734). The median owner-occupied home is valued at $150,300 (28% below the Iowa median), and median gross rent is $777 a month. The median age is 43.5; 22.1% of adults 25 and over hold a bachelor's degree or higher (31.4% across Iowa); the average commute takes 15 minutes.

Population13,096Cass13,096
Households5,844Cass5,844
Median age43.5Cass43.5Iowa38.6US 38.9
Median household income$63,013Cass$63,013Iowa$75,059US $80,734
Median home value$150,300Cass$150,300Iowa$208,000US $332,700
Median gross rent$777Cass$777Iowa$972US $1,413
Bachelor's degree or higher22.1%Cass22.1%Iowa31.4%US 35.7%
Mean commute15.1 minCass15.1 minIowa19.8 minUS 26.4 min
Population density23 / sq miCass23 / 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 Cass County

Largest towns in Cass County
TownZIP codesPopulation
Atlantic 1 6,763
Griswold 1 975
Anita 1 957
Lewis 1 461
Massena 1 383
Cumberland 1 302
Marne 1 98
Wiota 1 78

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 Cass County.

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

Every ZIP code in Cass County, with figures

ZIP codes in Cass County
ZIP City Type Population Median income Median home
50020 Anita , IA Standard 1,197 $75,417 $154,600
50022 Atlantic , IA Standard 8,526 $63,125 $157,600
50274 Wiota , IA Standard 234 $71,667 $162,100
50843 Cumberland , IA Standard 540 $56,125 $105,000
50853 Massena , IA Standard 716 $65,208 $169,100
51535 Griswold , IA Standard 1,697 $76,371 $152,300
51544 Lewis , IA Standard 793 $48,313 $81,000
51552 Marne , IA Standard 169 $90,000 $125,000

Cite this page

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

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