ZIP Code 57787 — Union Center, SD
57787 is a standard (street delivery) ZIP code serving Union Center, South Dakota, in Meade 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 57787 at a glance
| ZIP code | 57787 |
|---|---|
| Primary city | Union Center |
| State | South Dakota (SD) |
| County | Meade FIPS 46093 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Denver |
| Population | 487 |
| Coordinates | 44.664300, -102.660970 |
How ZIP+4 works in 57787
The four digits after the hyphen encode a delivery segment inside 57787. 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 57787 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 57787.
| ZIP | City | Distance |
|---|---|---|
| 57737 | Enning, SD | 10.1 mi |
| 57792 | White Owl, SD | 15.3 mi |
| 57758 | Mud Butte, SD | 22.8 mi |
| 57788 | Vale, SD | 27.5 mi |
| 57791 | Wasta, SD | 30.6 mi |
| 57761 | New Underwood, SD | 31.1 mi |
| 57785 | Sturgis, SD | 32 mi |
| 57626 | Faith, SD | 33.1 mi |
| 57719 | Box Elder, SD | 33.8 mi |
Questions about 57787
What is the ZIP+4 code for 57787?
57787 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 57787, you need to look up a specific street address to get them.
What city is 57787?
57787 is assigned to Union Center, South Dakota, in Meade 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.