Mason Ohio ZIP Codes
Mason holds a single ZIP code.
Every ZIP code in Mason
| ZIP code | County |
|---|---|
| 45040 | Warren County |
We do not publish a delivery type (standard, PO box, unique) or a neighbourhood for each ZIP. USPS delivery-type products are licensed, and no clean-rights source maps ZIP codes to neighbourhoods — so the Mason codes above are listed without a column we would have to invent.
Scope every ZIP code recorded for Mason. Source GeoNames US postal codes (2026-07 postal dump) and Census 2024 county Gazetteer (2024 Gazetteer). Updated . ZIP codes are delivery-route groupings, not areas; the boundaries implied by any ZIP map are approximations.
How these codes cluster
Every Mason ZIP code begins 450. Those first three digits identify the sectional center facility that processes mail for this part of Ohio. Statewide that range covers 39 ZIP codes, so Mason accounts for 3% of it.
Every Ohio ZIP prefix and the region it covers →
Area codes covering Mason
ZIP codes and area codes are separate systems — one routes mail, the other routes calls — and they do not share boundaries. The codes below serve the same ground Mason occupies.
Mason Ohio area codes in full →
Where Mason's ZIP codes sit
- Reference points and footprint
- Not an official NANPA boundary
- Not a USPS delivery area
Cities near Mason
| City | Distance | ZIP codes |
|---|---|---|
| South Lebanon Ohio ZIP codes | 4.1 mi | 1 ZIP code |
| West Chester Ohio ZIP codes | 6.0 mi | 2 ZIP codes |
| Lebanon Ohio ZIP codes | 6.0 mi | 1 ZIP code |
| Maineville Ohio ZIP codes | 6.6 mi | 1 ZIP code |
| Loveland Ohio ZIP codes | 6.6 mi | 1 ZIP code |
| Monroe Ohio ZIP codes | 7.0 mi | 1 ZIP code |
| Morrow Ohio ZIP codes | 9.4 mi | 1 ZIP code |
| Middletown Ohio ZIP codes | 11 mi | 2 ZIP codes |
Straight-line distance between place reference points, not driving distance. Where a place has no Census Gazetteer point, its postal centroid is used instead.