ZIP Code 59521 — Box Elder, MT
59521 is a standard (street delivery) ZIP code serving Box Elder, Montana, in Hill 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 59521 at a glance
| ZIP code | 59521 |
|---|---|
| Primary city | Box Elder |
| State | Montana (MT) |
| County | Hill FIPS 30041 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Denver |
| Population | 3,529 |
| Coordinates | 48.304890, -109.972000 |
How ZIP+4 works in 59521
The four digits after the hyphen encode a delivery segment inside 59521. 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 59521 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 59521.
| ZIP | City | Distance |
|---|---|---|
| 59520 | Big Sandy, MT | 18.5 mi |
| 59532 | Kremlin, MT | 20.2 mi |
| 59525 | Gildford, MT | 27.7 mi |
| 59501 | Havre, MT | 28.3 mi |
| 59460 | Loma, MT | 29.2 mi |
| 59528 | Hingham, MT | 30.3 mi |
| 59540 | Rudyard, MT | 34.2 mi |
Questions about 59521
What is the ZIP+4 code for 59521?
59521 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 59521, you need to look up a specific street address to get them.
What city is 59521?
59521 is assigned to Box Elder, Montana, in Hill 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.