Every ZIP code in the United States, with weather, radar, trivia and the numbers behind it. Five digits since 1963!

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zipcodes.pro — STATE/IA/COUNTY/MONONA

Monona County, IA ZIP codes

There are 9 ZIP codes in Monona County, IA, in 9 towns, from 51010 to 51572. The largest are 51040 (Onawa), 51034 (Mapleton) and 51063 (Whiting). 1 more crosses into it from a neighbouring county: 51026.

The county seat is Onawa.

ZIP codes
9
Partly in it
1 more
Towns
9
County seat
Onawa
County FIPS
19133
State
Iowa
Population
8,557
Median household income
$68,377
Land area
694 sq mi

Monona County ZIP codes by town

Onawa (county seat)
51040

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 Monona County

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

Map of Monona County ZIP codes

510105103451040510515106051063515235155851572

The ZIP codes of Monona 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.

Monona County in numbers

About 8,557 people live in Monona County, in 3,878 households, the 85th most populous of Iowa's 99 counties. The median household income is $68,377 a year, 9% below the Iowa median of $75,059 (US: $80,734). The median owner-occupied home is valued at $142,900 (31% below the Iowa median), and median gross rent is $855 a month. The median age is 43.7; 19.6% of adults 25 and over hold a bachelor's degree or higher (31.4% across Iowa); the average commute takes 23 minutes.

Population8,557Monona8,557
Households3,878Monona3,878
Median age43.7Monona43.7Iowa38.6US 38.9
Median household income$68,377Monona$68,377Iowa$75,059US $80,734
Median home value$142,900Monona$142,900Iowa$208,000US $332,700
Median gross rent$855Monona$855Iowa$972US $1,413
Bachelor's degree or higher19.6%Monona19.6%Iowa31.4%US 35.7%
Mean commute22.6 minMonona22.6 minIowa19.8 minUS 26.4 min
Population density12 / sq miMonona12 / 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 Monona County

Largest towns in Monona County
TownZIP codesPopulation
Onawa 1 2,839
Mapleton 1 989
Whiting 1 777
Ute 1 351
Blencoe 1 280
Moorhead 1 195
Castana 1 162
Soldier 1 133
Rodney 1 39

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 Monona County.

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

Every ZIP code in Monona County, with figures

ZIP codes in Monona County
ZIP City Type Population Median income Median home
51010 Castana , IA Standard 425 $89,063 $114,800
51034 Mapleton , IA Standard 1,674 $66,375 $120,500
51040 Onawa , IA Standard 3,500 $71,179 $151,600
51051 Rodney , IA Standard 39 $51,563 $170,800
51060 Ute , IA Standard 706 $52,500 $99,400
51063 Whiting , IA Standard 1,072 $80,750 $159,500
51523 Blencoe , IA Standard 379 $82,625 $136,800
51558 Moorhead , IA Standard 549 $77,417 $100,000
51572 Soldier , IA Standard 371 $69,500 $101,300

Cite this page

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

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