ZIP Code 57730

57730 is one of South Dakota's ZIP codes, delivering to addresses in Custer, Custer County.

City: Custer
County: Custer County
State: South Dakota
Prefix: 577xx

Where this code sits

57730 is part of the 577xx range, the group of codes handled by one mail processing centre. It is the only ZIP code delivering to Custer.

Custer South Dakota ZIP codes →

Area codes over the same ground

Postal and telephone geography are drawn separately, so these codes cover the area 57730 delivers to without sharing its boundary.

605 Area code 605

ZIP codes nearest 57730

The ZIP codes whose reference points sit closest to 57730.
ZIP code	Distance	Delivers to
ZIP code 57773	9.1 mi	Pringle, SD
ZIP code 57738	11 mi	Fairburn, SD
ZIP code 57722	12 mi	Buffalo Gap, SD
ZIP code 57744	16 mi	Hermosa, SD
ZIP code 57751	16 mi	Keystone, SD
ZIP code 57747	16 mi	Hot Springs, SD
ZIP code 57745	21 mi	Hill City, SD
ZIP code 57766	22 mi	Oral, SD

Straight-line distance between place reference points, not driving distance. Where a place has no Census Gazetteer point, its postal centroid is used instead.

Each point is the reference point for 57730, plotted from its record coordinates.

Reference points and footprint
Not an official NANPA boundary
Not a USPS delivery area

Scope ZIP code 57730. Source GeoNames US postal codes (2026-07 postal dump) and Census 2024 county Gazetteer (2024 Gazetteer). Updated 15 July 2026. A ZIP code is a set of delivery routes, not an area; the point shown is a record coordinate, not a centre.