ZIP Code 45440 — Dayton, OH
45440 is a standard (street delivery) ZIP code serving Dayton, Ohio, in Greene 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 45440 at a glance
| ZIP code | 45440 |
|---|---|
| Primary city | Dayton |
| State | Ohio (OH) |
| County | Greene FIPS 39057 |
| ZIP type | Standard (street delivery) |
| Time zone | America/New_York |
| Population | 22,358 |
| Coordinates | 39.674980, -84.100010 |
How ZIP+4 works in 45440
The four digits after the hyphen encode a delivery segment inside 45440. 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 45440 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.
Other ZIP codes in Dayton
Nearby ZIP codes
Showing the closest twelve. See every ZIP code within 25 miles of 45440.
| ZIP | City | Distance |
|---|---|---|
| 45430 | Dayton, OH | 2.7 mi |
| 45305 | Bellbrook, OH | 2.9 mi |
| 45420 | Dayton, OH | 3.4 mi |
| 45429 | Dayton, OH | 3.4 mi |
| 45459 | Dayton, OH | 4.1 mi |
| 45419 | Dayton, OH | 4.5 mi |
| 45432 | Dayton, OH | 4.5 mi |
| 45301 | Alpha, OH | 4.8 mi |
| 45434 | Dayton, OH | 5 mi |
| 45370 | Spring Valley, OH | 5.6 mi |
| 45409 | Dayton, OH | 5.8 mi |
| 45410 | Dayton, OH | 5.9 mi |
Questions about 45440
What is the ZIP+4 code for 45440?
45440 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 45440, you need to look up a specific street address to get them.
What city is 45440?
45440 is assigned to Dayton, Ohio, in Greene 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.