ZIP Code 61261 — Lyndon, IL
61261 is a standard (street delivery) ZIP code serving Lyndon, 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 61261 at a glance
| ZIP code | 61261 |
|---|---|
| Primary city | Lyndon |
| State | Illinois (IL) |
| County | Whiteside FIPS 17195 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Population | 656 |
| Coordinates | 41.729280, -89.911660 |
How ZIP+4 works in 61261
The four digits after the hyphen encode a delivery segment inside 61261. 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 61261 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 61261.
| ZIP | City | Distance |
|---|---|---|
| 61270 | Morrison, IL | 7.5 mi |
| 61251 | Fenton, IL | 8.3 mi |
| 61277 | Prophetstown, IL | 8.7 mi |
| 61037 | Galt, IL | 8.8 mi |
| 61250 | Erie, IL | 10.9 mi |
| 61071 | Rock Falls, IL | 10.9 mi |
| 61283 | Tampico, IL | 11.5 mi |
| 61081 | Sterling, IL | 12 mi |
| 61252 | Fulton, IL | 13.4 mi |
| 61243 | Deer Grove, IL | 14.2 mi |
| 61258 | Hooppole, IL | 14.3 mi |
| 61230 | Albany, IL | 15.6 mi |
Questions about 61261
What is the ZIP+4 code for 61261?
61261 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 61261, you need to look up a specific street address to get them.
What city is 61261?
61261 is assigned to Lyndon, 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.