ZIP Code 57630 — Glencross, SD
57630 is a standard (street delivery) ZIP code serving Glencross, South Dakota, in Dewey 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 57630 at a glance
| ZIP code | 57630 |
|---|---|
| Primary city | Glencross |
| State | South Dakota (SD) |
| County | Dewey FIPS 46041 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Denver |
| Population | 11 |
| Coordinates | 45.363580, -100.891920 |
How ZIP+4 works in 57630
The four digits after the hyphen encode a delivery segment inside 57630. 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 57630 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 57630.
| ZIP | City | Distance |
|---|---|---|
| 57661 | Whitehorse, SD | 7.3 mi |
| 57656 | Timber Lake, SD | 11.2 mi |
| 57657 | Trail City, SD | 11.9 mi |
| 57652 | Ridgeview, SD | 18.4 mi |
| 57601 | Mobridge, SD | 18.5 mi |
| 57639 | Little Eagle, SD | 22.2 mi |
| 57658 | Wakpala, SD | 25.9 mi |
| 57625 | Eagle Butte, SD | 28.5 mi |
| 57621 | Bullhead, SD | 29.4 mi |
| 57642 | Mclaughlin, SD | 30.3 mi |
| 57636 | Lantry, SD | 35.7 mi |
Questions about 57630
What is the ZIP+4 code for 57630?
57630 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 57630, you need to look up a specific street address to get them.
What city is 57630?
57630 is assigned to Glencross, South Dakota, in Dewey 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.