ZIP Code 57520 — Agar, SD
57520 is a standard (street delivery) ZIP code serving Agar, South Dakota, in Sully 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 57520 at a glance
| ZIP code | 57520 |
|---|---|
| Primary city | Agar |
| State | South Dakota (SD) |
| County | Sully FIPS 46119 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Population | 118 |
| Coordinates | 44.841590, -100.164470 |
How ZIP+4 works in 57520
The four digits after the hyphen encode a delivery segment inside 57520. 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 57520 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 57520.
| ZIP | City | Distance |
|---|---|---|
| 57564 | Onida, SD | 11 mi |
| 57442 | Gettysburg, SD | 14.9 mi |
| 57501 | Pierre, SD | 22.4 mi |
| 57455 | Lebanon, SD | 23.2 mi |
| 57522 | Blunt, SD | 24.9 mi |
| 57450 | Hoven, SD | 30.4 mi |
| 57420 | Akaska, SD | 30.6 mi |
| 57652 | Ridgeview, SD | 32.8 mi |
| 57536 | Harrold, SD | 35.3 mi |
| 57475 | Tolstoy, SD | 37.7 mi |
| 57540 | Holabird, SD | 37.8 mi |
| 57532 | Fort Pierre, SD | 38.5 mi |
Questions about 57520
What is the ZIP+4 code for 57520?
57520 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 57520, you need to look up a specific street address to get them.
What city is 57520?
57520 is assigned to Agar, South Dakota, in Sully 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.