ZIP Code 54521 — Eagle River, WI
54521 is a standard (street delivery) ZIP code serving Eagle River, Wisconsin, in Vilas 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 54521 at a glance
| ZIP code | 54521 |
|---|---|
| Primary city | Eagle River |
| State | Wisconsin (WI) |
| County | Vilas FIPS 55125 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Population | 8,551 |
| Coordinates | 45.916200, -89.254510 |
How ZIP+4 works in 54521
The four digits after the hyphen encode a delivery segment inside 54521. 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 54521 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 54521.
| ZIP | City | Distance |
|---|---|---|
| 54519 | Conover, WI | 9.5 mi |
| 54562 | Three Lakes, WI | 11 mi |
| 54558 | Saint Germain, WI | 11.7 mi |
| 54554 | Phelps, WI | 13.3 mi |
| 54561 | Star Lake, WI | 14.7 mi |
| 54560 | Sayner, WI | 15.3 mi |
| 54539 | Lake Tomahawk, WI | 17.2 mi |
| 54540 | Land O'lakes, WI | 17.6 mi |
| 54501 | Rhinelander, WI | 18.2 mi |
| 54568 | Woodruff, WI | 20.3 mi |
| 49969 | Watersmeet, MI | 22.8 mi |
| 54512 | Boulder Junction, WI | 23.4 mi |
Questions about 54521
What is the ZIP+4 code for 54521?
54521 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 54521, you need to look up a specific street address to get them.
What city is 54521?
54521 is assigned to Eagle River, Wisconsin, in Vilas 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.