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/OK/COUNTY/HARPER

Harper County, OK ZIP codes

Harper County, OK has 2 ZIP codes, in 2 towns: 73834 and 73855. 2 more cross into it from neighbouring counties: 73801 and 73848.

The county seat is Buffalo.

ZIP codes
2
Partly in it
2 more
Towns
2
County seat
Buffalo
County FIPS
40059
Population
3,203
Median household income
$64,053
Land area
1,039 sq mi

Harper County ZIP codes by town

Buffalo (county seat)
73834

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 Harper County

These ZIP codes lie mostly in a neighbouring county but each cover a twentieth or more of Harper County.

Map of Harper County ZIP codes

7383473855

The ZIP codes of Harper 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.

Harper County in numbers

About 3,203 people live in Harper County, in 1,333 households, the 75th most populous of Oklahoma's 77 counties. The median household income is $64,053 a year, about the same as the Oklahoma median of $65,039 (US: $80,734). The median owner-occupied home is valued at $99,200 (50% below the Oklahoma median), and median gross rent is $828 a month. The median age is 40.9; 29.3% of adults 25 and over hold a bachelor's degree or higher (28.3% across Oklahoma); the average commute takes 19 minutes.

Population3,203Harper3,203
Households1,333Harper1,333
Median age40.9Harper40.9Oklahoma37.0US 38.9
Median household income$64,053Harper$64,053Oklahoma$65,039US $80,734
Median home value$99,200Harper$99,200Oklahoma$199,800US $332,700
Median gross rent$828Harper$828Oklahoma$1,014US $1,413
Bachelor's degree or higher29.3%Harper29.3%Oklahoma28.3%US 35.7%
Mean commute19.4 minHarper19.4 minOklahoma22.4 minUS 26.4 min
Population density3 / sq miHarper3 / 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 Harper County

Largest towns in Harper County
TownZIP codesPopulation
Buffalo 1 1,092
Rosston 1 58

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 Harper County.

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

Every ZIP code in Harper County, with figures

ZIP codes in Harper County
ZIP City Type Population Median income Median home
73834 Buffalo , OK Standard 1,544 $72,500 $91,900
73855 Rosston , OK Standard 253 $63,333 $185,700

Cite this page

zipcodes.pro. “Harper County ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/ok/county/harper

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