ZIP Code 57440

57440 is one of South Dakota's ZIP codes, delivering to addresses in Frankfort, Spink County.

City: Frankfort
County: Spink County
State: South Dakota
Prefix: 574xx

Where this code sits

57440 is part of the 574xx range, the group of codes handled by one mail processing centre. It is the only ZIP code delivering to Frankfort.

Frankfort South Dakota ZIP codes →

Area codes over the same ground

Postal and telephone geography are drawn separately, so these codes cover the area 57440 delivers to without sharing its boundary.

605 Area code 605

ZIP codes nearest 57440

The ZIP codes whose reference points sit closest to 57440.
ZIP code	Distance	Delivers to
ZIP code 57436	9.8 mi	Doland, SD
ZIP code 57469	12 mi	Redfield, SD
ZIP code 57476	14 mi	Tulare, SD
ZIP code 57424	17 mi	Ashton, SD
ZIP code 57348	17 mi	Hitchcock, SD
ZIP code 57477	19 mi	Turton, SD
ZIP code 57258	19 mi	Raymond, SD
ZIP code 57322	21 mi	Carpenter, 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 57440, plotted from its record coordinates.

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

Scope ZIP code 57440. 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.