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zipcodes.pro — CITY/SD/KEYSTONE

Keystone ZIP code, South Dakota

The ZIP code for Keystone, SD is 57751, and its area code is 605.

USPS city name
1 ZIP code
Population
336
Area code
605

Keystone in numbers

About 336 people live in Keystone, in 107 households. The median household income is $64,702 a year, 14% below the South Dakota median of $75,081 (US: $80,734). The median owner-occupied home is valued at $263,900 (about the same as the South Dakota median), and median gross rent is $546 a month. The median age is 38.1; 13.5% of adults 25 and over hold a bachelor's degree or higher (31.9% across South Dakota); the average commute takes 33 minutes.

Population336Keystone336
Households107Keystone107
Median age38.1Keystone38.1South Dakota38.0US 38.9
Median household income$64,702Keystone$64,702South Dakota$75,081US $80,734
Median home value$263,900Keystone$263,900South Dakota$257,400US $332,700
Median gross rent$546Keystone$546South Dakota$946US $1,413
Bachelor's degree or higher13.5%Keystone13.5%South Dakota31.9%US 35.7%
Mean commute32.6 minKeystone32.6 minSouth Dakota17.8 minUS 26.4 min
Population density112 / sq miKeystone112 / sq mi

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

ZIP codes addressed as Keystone

ZIP codes with the USPS city name Keystone
ZIP City Type Population Median income Median home
57751 Keystone , SD Standard 893 $97,969 $473,500

Map of Keystone ZIP codes

57751

The ZIP codes of Keystone, 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 Keystone

The nearest larger towns are Hill City (834 people, 7.5 mi), Colonial Pine Hills (2,609 people, 9.9 mi) and Custer (2,341 people, 12 mi).

Towns near Keystone
TownPopulationDistance
Colonial Pine Hills 2,609 9.9 mi
Rapid City 77,946 16.0 mi
Blackhawk 2,934 18.3 mi
Rapid Valley 6,975 19.3 mi
Summerset 3,022 21.0 mi
Box Elder 12,902 22.8 mi

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

Cite this page

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

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