ZIP Code 57368 — Plankinton, SD
57368 is a standard (street delivery) ZIP code serving Plankinton, South Dakota, in Aurora 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 57368 at a glance
| ZIP code | 57368 |
|---|---|
| Primary city | Plankinton |
| State | South Dakota (SD) |
| County | Aurora FIPS 46003 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Population | 1,068 |
| Coordinates | 43.751170, -98.475930 |
How ZIP+4 works in 57368
The four digits after the hyphen encode a delivery segment inside 57368. 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 57368 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 57368.
| ZIP | City | Distance |
|---|---|---|
| 57363 | Mount Vernon, SD | 11.9 mi |
| 57383 | White Lake, SD | 12.1 mi |
| 57375 | Stickney, SD | 13 mi |
| 57359 | Letcher, SD | 19 mi |
| 57344 | Harrison, SD | 21.6 mi |
| 57301 | Mitchell, SD | 21.8 mi |
| 57328 | Corsica, SD | 21.9 mi |
| 57385 | Woonsocket, SD | 22.1 mi |
| 57358 | Lane, SD | 22.5 mi |
| 57364 | New Holland, SD | 23 mi |
| 57382 | Wessington Springs, SD | 23.2 mi |
| 57355 | Kimball, SD | 23.7 mi |
Questions about 57368
What is the ZIP+4 code for 57368?
57368 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 57368, you need to look up a specific street address to get them.
What city is 57368?
57368 is assigned to Plankinton, South Dakota, in Aurora 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.