ZIP Code 45320 — Eaton, OH
45320 is a standard (street delivery) ZIP code serving Eaton, Ohio, in Preble County. To mail something here you only need these five digits — but the four-digit extension narrows delivery to a single point, and it is what USPS bulk postage discounts are priced on.
ZIP code 45320 at a glance
| ZIP code | 45320 |
|---|---|
| Primary city | Eaton |
| State | Ohio (OH) |
| County | Preble FIPS 39135 |
| ZIP type | Standard (street delivery) |
| Time zone | America/New_York |
| Population | 15,454 |
| Coordinates | 39.746730, -84.689320 |
How ZIP+4 works in 45320
The four digits after the hyphen encode a delivery segment inside 45320. In practice one segment usually means:
- One side of one block — odd numbers on a street between two cross streets
- A single large building, or one floor of it
- A group of PO boxes, sometimes a single box
- A single business that receives enough mail to warrant its own code
That is why 45320 has no single ZIP+4: two neighbors across the street from each other usually have different ones. Enter a street address above and we will return the exact nine-digit code along with the standardized USPS address format.
Nearby ZIP codes
Showing the closest twelve. See every ZIP code within 25 miles of 45320.
| ZIP | City | Distance |
|---|---|---|
| 45311 | Camden, OH | 8.3 mi |
| 45321 | Eldorado, OH | 8.6 mi |
| 47324 | Boston, IN | 8.6 mi |
| 45381 | West Alexandria, OH | 8.8 mi |
| 45347 | New Paris, OH | 10.2 mi |
| 45338 | Lewisburg, OH | 10.6 mi |
| 45330 | Gratis, OH | 10.9 mi |
| 45382 | West Manchester, OH | 11 mi |
| 45003 | College Corner, OH | 12.2 mi |
| 47374 | Richmond, IN | 12.2 mi |
| 45070 | West Elkton, OH | 12.9 mi |
| 45064 | Somerville, OH | 13.2 mi |
Questions about 45320
What is the ZIP+4 code for 45320?
45320 is the five-digit ZIP code. The ZIP+4 adds four more digits that identify a specific delivery point — usually one side of a city block, a single building, or a group of PO boxes. Because those four digits change from address to address within 45320, you need to look up a specific street address to get them.
What city is 45320?
45320 is assigned to Eaton, Ohio, in Preble County.
Do I need to use the ZIP+4?
It is optional for ordinary mail, but it speeds up sorting and it is required for most USPS bulk-mail postage discounts. Many address-verification and e-commerce systems also use ZIP+4 to confirm a delivery point exists.
Need thousands of these?
Upload a CSV and get ZIP+4, county, carrier route, and delivery-point data appended to every row — or call the API directly.