ZIP Code 57451 — Ipswich, SD
57451 is a standard (street delivery) ZIP code serving Ipswich, South Dakota, in Edmunds 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 57451 at a glance
| ZIP code | 57451 |
|---|---|
| Primary city | Ipswich |
| State | South Dakota (SD) |
| County | Edmunds FIPS 46045 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Population | 2,485 |
| Coordinates | 45.434880, -98.934730 |
How ZIP+4 works in 57451
The four digits after the hyphen encode a delivery segment inside 57451. 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 57451 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 57451.
| ZIP | City | Distance |
|---|---|---|
| 57460 | Mansfield, SD | 17.1 mi |
| 57435 | Cresbard, SD | 18.4 mi |
| 57471 | Roscoe, SD | 18.4 mi |
| 57401 | Aberdeen, SD | 19.8 mi |
| 57481 | Westport, SD | 19.8 mi |
| 57456 | Leola, SD | 20 mi |
| 57465 | Northville, SD | 23.4 mi |
| 57479 | Warner, SD | 25.7 mi |
| 57448 | Hosmer, SD | 26.4 mi |
| 57438 | Faulkton, SD | 27.4 mi |
| 57426 | Barnard, SD | 29.7 mi |
| 57466 | Onaka, SD | 30.1 mi |
Questions about 57451
What is the ZIP+4 code for 57451?
57451 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 57451, you need to look up a specific street address to get them.
What city is 57451?
57451 is assigned to Ipswich, South Dakota, in Edmunds 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.