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zipcodes.pro — CITY/SD/EUREKA

Eureka ZIP code, South Dakota

The ZIP code for Eureka, SD is 57437, and its area code is 605.

USPS city name
1 ZIP code
Population
778
Area code
605

Eureka in numbers

About 778 people live in Eureka, in 400 households. The median household income is $47,583 a year, 37% below the South Dakota median of $75,081 (US: $80,734). The median owner-occupied home is valued at $78,200 (70% below the South Dakota median), and median gross rent is $557 a month. The median age is 63.1; 21.9% of adults 25 and over hold a bachelor's degree or higher (31.9% across South Dakota); the average commute takes 19 minutes.

Population778Eureka778
Households400Eureka400
Median age63.1Eureka63.1South Dakota38.0US 38.9
Median household income$47,583Eureka$47,583South Dakota$75,081US $80,734
Median home value$78,200Eureka$78,200South Dakota$257,400US $332,700
Median gross rent$557Eureka$557South Dakota$946US $1,413
Bachelor's degree or higher21.9%Eureka21.9%South Dakota31.9%US 35.7%
Mean commute18.8 minEureka18.8 minSouth Dakota17.8 minUS 26.4 min
Population density834 / sq miEureka834 / sq mi

U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates, for the census place Eureka city. Survey estimates carry margins of error, wider for small places. Sources and methods.

ZIP codes addressed as Eureka

ZIP codes with the USPS city name Eureka
ZIP City Type Population Median income Median home
57437 Eureka , SD Standard 1,074 $49,276 $86,700

Map of Eureka ZIP codes

57437

The ZIP codes of Eureka, SD, 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.

Towns near Eureka

The nearest larger towns are Wishek, ND (849 people, 34 mi), Ipswich (1,048 people, 36 mi) and Mobridge (2,932 people, 42 mi).

More nearby: every ZIP code in McPherson County · South Dakota ZIP codes

Cite this page

zipcodes.pro. “Eureka, SD ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/city/sd/eureka

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