ZIP Code 45312

45312 is one of Ohio's ZIP codes, delivering to addresses in Casstown, Miami County.

City: Casstown
County: Miami County
State: Ohio
Prefix: 453xx

Where this code sits

45312 is part of the 453xx range, the group of codes handled by one mail processing centre. It is the only ZIP code delivering to Casstown.

Casstown Ohio ZIP codes →

Area codes over the same ground

Postal and telephone geography are drawn separately, so these codes cover the area 45312 delivers to without sharing its boundary.

ZIP codes nearest 45312

The ZIP codes whose reference points sit closest to 45312.
ZIP code	Distance	Delivers to
ZIP code 45389	4.5 mi	Christiansburg, OH
ZIP code 45326	5.1 mi	Fletcher, OH
ZIP code 45373	5.5 mi	Troy, OH
ZIP code 45317	6.7 mi	Conover, OH
ZIP code 45374	6.8 mi	Troy, OH
ZIP code 43072	8.1 mi	Saint Paris, OH
ZIP code 45356	9.3 mi	Piqua, OH
ZIP code 45371	9.5 mi	Tipp City, 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 45312, plotted from its record coordinates.

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

Scope ZIP code 45312. 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.