ZIP Code 61102 — Rockford, IL
61102 is a standard (street delivery) ZIP code serving Rockford, Illinois, in Winnebago 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 61102 at a glance
| ZIP code | 61102 |
|---|---|
| Primary city | Rockford |
| State | Illinois (IL) |
| County | Winnebago FIPS 17201 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Population | 15,937 |
| Coordinates | 42.229950, -89.156320 |
How ZIP+4 works in 61102
The four digits after the hyphen encode a delivery segment inside 61102. 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 61102 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.
Other ZIP codes in Rockford
Nearby ZIP codes
Showing the closest twelve. See every ZIP code within 25 miles of 61102.
| ZIP | City | Distance |
|---|---|---|
| 61104 | Rockford, IL | 4.2 mi |
| 61109 | Rockford, IL | 5.8 mi |
| 61088 | Winnebago, IL | 5.8 mi |
| 61101 | Rockford, IL | 7.4 mi |
| 61084 | Stillman Valley, IL | 7.9 mi |
| 61108 | Rockford, IL | 8.1 mi |
| 61107 | Rockford, IL | 8.6 mi |
| 61010 | Byron, IL | 8.6 mi |
| 61103 | Rockford, IL | 8.8 mi |
| 61020 | Davis Junction, IL | 8.8 mi |
| 61112 | Rockford, IL | 9.3 mi |
| 61077 | Seward, IL | 9.8 mi |
Questions about 61102
What is the ZIP+4 code for 61102?
61102 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 61102, you need to look up a specific street address to get them.
What city is 61102?
61102 is assigned to Rockford, Illinois, in Winnebago 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.