ZIP Code 57430 — Britton, SD
57430 is a standard (street delivery) ZIP code serving Britton, South Dakota, in Marshall 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 57430 at a glance
| ZIP code | 57430 |
|---|---|
| Primary city | Britton |
| State | South Dakota (SD) |
| County | Marshall FIPS 46091 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Population | 1,828 |
| Coordinates | 45.822030, -97.722050 |
How ZIP+4 works in 57430
The four digits after the hyphen encode a delivery segment inside 57430. 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 57430 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 57430.
| ZIP | City | Distance |
|---|---|---|
| 57421 | Amherst, SD | 10.1 mi |
| 58043 | Havana, ND | 13.9 mi |
| 57247 | Lake City, SD | 14.6 mi |
| 57454 | Langford, SD | 14.8 mi |
| 58017 | Cogswell, ND | 16.3 mi |
| 57432 | Claremont, SD | 17.4 mi |
| 58032 | Forman, ND | 17.6 mi |
| 57270 | Veblen, SD | 18.9 mi |
| 58067 | Rutland, ND | 20.4 mi |
| 57446 | Hecla, SD | 21 mi |
| 57232 | Eden, SD | 21.5 mi |
| 57261 | Roslyn, SD | 22.3 mi |
Questions about 57430
What is the ZIP+4 code for 57430?
57430 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 57430, you need to look up a specific street address to get them.
What city is 57430?
57430 is assigned to Britton, South Dakota, in Marshall 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.