ZIP Code 61237 — Buffalo Prairie, IL
61237 is a standard (street delivery) ZIP code serving Buffalo Prairie, Illinois, in Rock Island 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 61237 at a glance
| ZIP code | 61237 |
|---|---|
| Primary city | Buffalo Prairie |
| State | Illinois (IL) |
| County | Rock Island FIPS 17161 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Coordinates | 41.341750, -90.862210 |
How ZIP+4 works in 61237
The four digits after the hyphen encode a delivery segment inside 61237. 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 61237 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 61237.
| ZIP | City | Distance |
|---|---|---|
| 61259 | Illinois City, IL | 4.7 mi |
| 61284 | Taylor Ridge, IL | 6.8 mi |
| 61279 | Reynolds, IL | 7 mi |
| 61260 | Joy, IL | 7 mi |
| 52759 | Montpelier, IA | 8.6 mi |
| 61232 | Andalusia, IL | 9.3 mi |
| 61272 | New Boston, IL | 10 mi |
| 52728 | Buffalo, IA | 10.7 mi |
| 61231 | Aledo, IL | 11.5 mi |
| 52726 | Blue Grass, IA | 11.7 mi |
| 52761 | Muscatine, IA | 12.1 mi |
| 52749 | Fruitland, IA | 13.9 mi |
Questions about 61237
What is the ZIP+4 code for 61237?
61237 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 61237, you need to look up a specific street address to get them.
What city is 61237?
61237 is assigned to Buffalo Prairie, Illinois, in Rock Island 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.