ZIP Code 57620

57620 is one of South Dakota's ZIP codes, delivering to addresses in Bison, Perkins County.

City: Bison
County: Perkins County
State: South Dakota
Prefix: 576xx

Where this code sits

57620 is part of the 576xx range, the group of codes handled by one mail processing centre. It is the only ZIP code delivering to Bison.

Bison South Dakota ZIP codes →

Area codes over the same ground

Postal and telephone geography are drawn separately, so these codes cover the area 57620 delivers to without sharing its boundary.

605 Area code 605

ZIP codes nearest 57620

The ZIP codes whose reference points sit closest to 57620.
ZIP code	Distance	Delivers to
ZIP code 57644	15 mi	Meadow, SD
ZIP code 57649	16 mi	Prairie City, SD
ZIP code 57640	25 mi	Lodgepole, SD
ZIP code 57638	31 mi	Lemmon, SD
ZIP code 57634	33 mi	Keldron, SD
ZIP code 57758	37 mi	Mud Butte, SD
ZIP code 58639	40 mi	Hettinger, ND
ZIP code 58649	47 mi	Reeder, ND

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 57620, plotted from its record coordinates.

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

Scope ZIP code 57620. 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.