ZIP Code 45820

45820 is one of Ohio's ZIP codes, delivering to addresses in Cairo, Allen County.

City: Cairo
County: Allen County
State: Ohio
Prefix: 458xx

Where this code sits

45820 is part of the 458xx range, the group of codes handled by one mail processing centre. It is the only ZIP code delivering to Cairo.

Cairo Ohio ZIP codes →

Area codes over the same ground

Postal and telephone geography are drawn separately, so these codes cover the area 45820 delivers to without sharing its boundary.

ZIP codes nearest 45820

The ZIP codes whose reference points sit closest to 45820.
ZIP code	Distance	Delivers to
ZIP code 45807	3.7 mi	Lima, OH
ZIP code 45802	4.4 mi	Lima, OH
ZIP code 45801	4.6 mi	Lima, OH
ZIP code 45893	4.9 mi	Vaughnsville, OH
ZIP code 45809	5.4 mi	Gomer, OH
ZIP code 45808	5.7 mi	Beaverdam, OH
ZIP code 45830	5.8 mi	Columbus Grove, OH
ZIP code 45805	7.0 mi	Lima, OH

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 45820, plotted from its record coordinates.

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

Scope ZIP code 45820. 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.