ZIP Code 57437 — Eureka, SD
57437 is a standard (street delivery) ZIP code serving Eureka, South Dakota, in McPherson 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 57437 at a glance
| ZIP code | 57437 |
|---|---|
| Primary city | Eureka |
| State | South Dakota (SD) |
| County | McPherson FIPS 46089 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Population | 1,074 |
| Coordinates | 45.783680, -99.618000 |
How ZIP+4 works in 57437
The four digits after the hyphen encode a delivery segment inside 57437. 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 57437 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 57437.
| ZIP | City | Distance |
|---|---|---|
| 57448 | Hosmer, SD | 15.2 mi |
| 58581 | Zeeland, ND | 20.1 mi |
| 57632 | Herreid, SD | 21 mi |
| 57452 | Java, SD | 21.5 mi |
| 58413 | Ashley, ND | 21.5 mi |
| 57646 | Mound City, SD | 22 mi |
| 57457 | Long Lake, SD | 23 mi |
| 57428 | Bowdle, SD | 23.2 mi |
| 58542 | Hague, ND | 26.1 mi |
| 57471 | Roscoe, SD | 29.7 mi |
| 58495 | Wishek, ND | 33.7 mi |
| 57472 | Selby, SD | 33.9 mi |
Questions about 57437
What is the ZIP+4 code for 57437?
57437 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 57437, you need to look up a specific street address to get them.
What city is 57437?
57437 is assigned to Eureka, South Dakota, in McPherson 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.