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zipcodes.pro — STATE/IA/COUNTY/OSCEOLA

Osceola County, IA ZIP codes

Osceola County, IA has 5 ZIP codes, in 5 towns: 51249, 51354, 51232, 51350 and 51345. 1 more crosses into it from a neighbouring county: 51346.

The county seat is Sibley.

ZIP codes
5
Partly in it
1 more
Towns
5
County seat
Sibley
County FIPS
19143
State
Iowa
Population
6,100
Median household income
$69,239
Land area
399 sq mi

Osceola County ZIP codes by town

Sibley (county seat)
51249

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 Osceola County

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

Map of Osceola County ZIP codes

5123251249513455135051354

The ZIP codes of Osceola 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.

Osceola County in numbers

About 6,100 people live in Osceola County, in 2,634 households, the 95th most populous of Iowa's 99 counties. The median household income is $69,239 a year, 8% below the Iowa median of $75,059 (US: $80,734). The median owner-occupied home is valued at $122,600 (41% below the Iowa median), and median gross rent is $797 a month. The median age is 43.1; 16.7% of adults 25 and over hold a bachelor's degree or higher (31.4% across Iowa); the average commute takes 18 minutes.

Population6,100Osceola6,100
Households2,634Osceola2,634
Median age43.1Osceola43.1Iowa38.6US 38.9
Median household income$69,239Osceola$69,239Iowa$75,059US $80,734
Median home value$122,600Osceola$122,600Iowa$208,000US $332,700
Median gross rent$797Osceola$797Iowa$972US $1,413
Bachelor's degree or higher16.7%Osceola16.7%Iowa31.4%US 35.7%
Mean commute18.2 minOsceola18.2 minIowa19.8 minUS 26.4 min
Population density15 / sq miOsceola15 / 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 Osceola County

Largest towns in Osceola County
TownZIP codesPopulation
Sibley 1 2,803
Ocheyedan 1 511
Ashton 1 461
Melvin 1 230
Harris 1 222

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 Osceola County.

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

Every ZIP code in Osceola County, with figures

ZIP codes in Osceola County
ZIP City Type Population Median income Median home
51232 Ashton , IA Standard 658 $82,917 $107,500
51249 Sibley , IA Standard 3,564 $61,500 $160,700
51345 Harris , IA Standard 347 $54,301 $141,700
51350 Melvin , IA Standard 383 $77,250 $79,300
51354 Ocheyedan , IA Standard 965 $72,639 $115,400

Cite this page

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

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