ZIP Code 45390 — Union City, OH
45390 is a standard (street delivery) ZIP code serving Union City, Ohio, in Darke 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 45390 at a glance
| ZIP code | 45390 |
|---|---|
| Primary city | Union City |
| State | Ohio (OH) |
| County | Darke FIPS 39037 |
| ZIP type | Standard (street delivery) |
| Time zone | America/New_York |
| Population | 3,432 |
| Coordinates | 40.218940, -84.767780 |
How ZIP+4 works in 45390
The four digits after the hyphen encode a delivery segment inside 45390. 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 45390 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 45390.
| ZIP | City | Distance |
|---|---|---|
| 47390 | Union City, IN | 4.2 mi |
| 45303 | Ansonia, OH | 5.9 mi |
| 47382 | Saratoga, IN | 8 mi |
| 45362 | Rossburg, OH | 8.5 mi |
| 45348 | New Weston, OH | 9.5 mi |
| 45331 | Greenville, OH | 10.6 mi |
| 45310 | Burkettsville, OH | 11.4 mi |
| 45352 | Palestine, OH | 11.7 mi |
| 47394 | Winchester, IN | 12.1 mi |
| 47381 | Salamonia, IN | 12.6 mi |
| 45350 | North Star, OH | 12.6 mi |
| 45846 | Fort Recovery, OH | 13.2 mi |
Questions about 45390
What is the ZIP+4 code for 45390?
45390 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 45390, you need to look up a specific street address to get them.
What city is 45390?
45390 is assigned to Union City, Ohio, in Darke 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.