ZIP Code 57634 — Keldron, SD
57634 is a standard (street delivery) ZIP code serving Keldron, South Dakota, in Corson 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 57634 at a glance
| ZIP code | 57634 |
|---|---|
| Primary city | Keldron |
| State | South Dakota (SD) |
| County | Corson FIPS 46031 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Denver |
| Population | 131 |
| Coordinates | 45.752310, -101.878950 |
How ZIP+4 works in 57634
The four digits after the hyphen encode a delivery segment inside 57634. 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 57634 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 57634.
| ZIP | City | Distance |
|---|---|---|
| 57645 | Morristown, SD | 13.4 mi |
| 57660 | Watauga, SD | 17.5 mi |
| 57638 | Lemmon, SD | 17.8 mi |
| 57644 | Meadow, SD | 22.9 mi |
| 57633 | Isabel, SD | 27.9 mi |
| 57641 | Mcintosh, SD | 29.2 mi |
Questions about 57634
What is the ZIP+4 code for 57634?
57634 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 57634, you need to look up a specific street address to get them.
What city is 57634?
57634 is assigned to Keldron, South Dakota, in Corson 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?
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