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/SD/COUNTY/BUFFALO

Buffalo County, SD ZIP codes

Buffalo County, SD has 2 ZIP codes, in 2 towns: 57339 and 57341. 2 more cross into it from a neighbouring county: 57325 and 57370.

The county seat is Gann Valley.

ZIP codes
2
Partly in it
2 more
Towns
2
County seat
Gann Valley
County FIPS
46017
Population
1,808
Median household income
$47,045
Land area
471 sq mi

Buffalo County ZIP codes by town

Gann Valley (county seat)
57341

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 Buffalo County

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

Map of Buffalo County ZIP codes

5733957341

The ZIP codes of Buffalo 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.

Buffalo County in numbers

About 1,808 people live in Buffalo County, in 508 households, the 59th most populous of South Dakota's 66 counties. The median household income is $47,045 a year, 37% below the South Dakota median of $75,081 (US: $80,734). The median owner-occupied home is valued at $117,800 (54% below the South Dakota median), and median gross rent is $540 a month. The median age is 22.8; 9.9% of adults 25 and over hold a bachelor's degree or higher (31.9% across South Dakota); the average commute takes 13 minutes.

Population1,808Buffalo1,808
Households508Buffalo508
Median age22.8Buffalo22.8South Dakota38.0US 38.9
Median household income$47,045Buffalo$47,045South Dakota$75,081US $80,734
Median home value$117,800Buffalo$117,800South Dakota$257,400US $332,700
Median gross rent$540Buffalo$540South Dakota$946US $1,413
Bachelor's degree or higher9.9%Buffalo9.9%South Dakota31.9%US 35.7%
Mean commute13.4 minBuffalo13.4 minSouth Dakota17.8 minUS 26.4 min
Population density4 / sq miBuffalo4 / 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 Buffalo County

Largest towns in Buffalo County
TownZIP codesPopulation
Fort Thompson 1 1,147
Gann Valley 1 6

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 Buffalo County.

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

Every ZIP code in Buffalo County, with figures

ZIP codes in Buffalo County
ZIP City Type Population Median income Median home
57339 Fort Thompson , SD Standard 1,390 $46,136 $121,700
57341 Gann Valley , SD Standard 79 — —

Cite this page

zipcodes.pro. “Buffalo County ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/sd/county/buffalo

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