ZIP Code 99111 — Colfax, WA
99111 is a standard (street delivery) ZIP code serving Colfax, Washington, in Whitman 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 99111 at a glance
| ZIP code | 99111 |
|---|---|
| Primary city | Colfax |
| State | Washington (WA) |
| County | Whitman FIPS 53075 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Los_Angeles |
| Population | 4,038 |
| Coordinates | 46.862810, -117.441320 |
How ZIP+4 works in 99111
The four digits after the hyphen encode a delivery segment inside 99111. 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 99111 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 99111.
| ZIP | City | Distance |
|---|---|---|
| 99102 | Albion, WA | 10.2 mi |
| 99174 | Steptoe, WA | 10.7 mi |
| 99163 | Pullman, WA | 14.1 mi |
| 99161 | Palouse, WA | 14.8 mi |
| 99130 | Garfield, WA | 15.3 mi |
| 99176 | Thornton, WA | 15.9 mi |
| 99125 | Endicott, WA | 17.4 mi |
| 99171 | Saint John, WA | 19.4 mi |
| 99158 | Oakesdale, WA | 20.9 mi |
| 99143 | Lacrosse, WA | 21.3 mi |
| 83844 | Moscow, ID | 22 mi |
| 83872 | Viola, ID | 22.1 mi |
Questions about 99111
What is the ZIP+4 code for 99111?
99111 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 99111, you need to look up a specific street address to get them.
What city is 99111?
99111 is assigned to Colfax, Washington, in Whitman 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.