ZIP Code 61081 — Sterling, IL
61081 is a standard (street delivery) ZIP code serving Sterling, Illinois, in Whiteside 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 61081 at a glance
| ZIP code | 61081 |
|---|---|
| Primary city | Sterling |
| State | Illinois (IL) |
| County | Whiteside FIPS 17195 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Population | 20,844 |
| Coordinates | 41.844250, -89.736130 |
How ZIP+4 works in 61081
The four digits after the hyphen encode a delivery segment inside 61081. 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 61081 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 61081.
| ZIP | City | Distance |
|---|---|---|
| 61037 | Galt, IL | 4.1 mi |
| 61071 | Rock Falls, IL | 8.4 mi |
| 61051 | Milledgeville, IL | 9.7 mi |
| 61091 | Woosung, IL | 10.4 mi |
| 61270 | Morrison, IL | 11.8 mi |
| 61014 | Chadwick, IL | 11.9 mi |
| 61261 | Lyndon, IL | 12 mi |
| 61064 | Polo, IL | 12.6 mi |
| 61021 | Dixon, IL | 13.3 mi |
| 61042 | Harmon, IL | 14.1 mi |
| 61243 | Deer Grove, IL | 15.9 mi |
| 61324 | Eldena, IL | 17.4 mi |
Questions about 61081
What is the ZIP+4 code for 61081?
61081 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 61081, you need to look up a specific street address to get them.
What city is 61081?
61081 is assigned to Sterling, Illinois, in Whiteside 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.