ZIP Code 51231

51231 is one of Iowa's ZIP codes, delivering to addresses in Archer, O'Brien County.

City: Archer
County: O'Brien County
State: Iowa
Prefix: 512xx

Where this code sits

51231 is part of the 512xx range, the group of codes handled by one mail processing centre. It is the only ZIP code delivering to Archer.

Archer Iowa ZIP codes →

Area codes over the same ground

Postal and telephone geography are drawn separately, so these codes cover the area 51231 delivers to without sharing its boundary.

712 Area code 712

ZIP codes nearest 51231

The ZIP codes whose reference points sit closest to 51231.
ZIP code	Distance	Delivers to
ZIP code 51245	5.3 mi	Primghar, IA
ZIP code 51248	6.3 mi	Sanborn, IA
ZIP code 51201	6.6 mi	Sheldon, IA
ZIP code 51238	9.1 mi	Hospers, IA
ZIP code 51046	10 mi	Paullina, IA
ZIP code 51022	13 mi	Granville, IA
ZIP code 51232	13 mi	Ashton, IA
ZIP code 51244	13 mi	Matlock, IA

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 51231, plotted from its record coordinates.

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

Scope ZIP code 51231. 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.