ZIP Code 99121 — Danville, WA
99121 is a standard (street delivery) ZIP code serving Danville, Washington, in Ferry 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 99121 at a glance
| ZIP code | 99121 |
|---|---|
| Primary city | Danville |
| State | Washington (WA) |
| County | Ferry FIPS 53019 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Los_Angeles |
| Population | 262 |
| Coordinates | 48.943820, -118.455680 |
How ZIP+4 works in 99121
The four digits after the hyphen encode a delivery segment inside 99121. 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 99121 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 99121.
| ZIP | City | Distance |
|---|---|---|
| 99146 | Laurier, WA | 7.2 mi |
| 99160 | Orient, WA | 8.7 mi |
| 99118 | Curlew, WA | 8.9 mi |
| 99150 | Malo, WA | 11.8 mi |
| 99141 | Kettle Falls, WA | 19.7 mi |
| 98859 | Wauconda, WA | 22.5 mi |
| 99166 | Republic, WA | 25 mi |
| 99126 | Evans, WA | 26.1 mi |
| 99151 | Marcus, WA | 26.3 mi |
Questions about 99121
What is the ZIP+4 code for 99121?
99121 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 99121, you need to look up a specific street address to get them.
What city is 99121?
99121 is assigned to Danville, Washington, in Ferry 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.