ZIP Code 66521

66521 is one of Kansas's ZIP codes, delivering to addresses in Onaga, Pottawatomie County.

City: Onaga
County: Pottawatomie County
State: Kansas
Prefix: 665xx

Where this code sits

66521 is part of the 665xx range, the group of codes handled by one mail processing centre. It is the only ZIP code delivering to Onaga.

Onaga Kansas ZIP codes →

Area codes over the same ground

Postal and telephone geography are drawn separately, so these codes cover the area 66521 delivers to without sharing its boundary.

785 Area code 785

ZIP codes nearest 66521

The ZIP codes whose reference points sit closest to 66521.
ZIP code	Distance	Delivers to
ZIP code 66432	5.0 mi	Havensville, KS
ZIP code 66540	11 mi	Soldier, KS
ZIP code 66417	14 mi	Corning, KS
ZIP code 66422	14 mi	Emmett, KS
ZIP code 66549	15 mi	Westmoreland, KS
ZIP code 66544	15 mi	Vermillion, KS
ZIP code 66428	17 mi	Goff, KS
ZIP code 66416	17 mi	Circleville, KS

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 66521, plotted from its record coordinates.

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

Scope ZIP code 66521. 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.