ZIP Code 98850 — Rock Island, WA
98850 is a standard (street delivery) ZIP code serving Rock Island, Washington, in Douglas 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 98850 at a glance
| ZIP code | 98850 |
|---|---|
| Primary city | Rock Island |
| State | Washington (WA) |
| County | Douglas FIPS 53017 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Los_Angeles |
| Population | 2,032 |
| Coordinates | 47.400480, -120.034590 |
How ZIP+4 works in 98850
The four digits after the hyphen encode a delivery segment inside 98850. 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 98850 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 98850.
| ZIP | City | Distance |
|---|---|---|
| 98845 | Palisades, WA | 6.2 mi |
| 98802 | East Wenatchee, WA | 8.8 mi |
| 98828 | Malaga, WA | 9.5 mi |
| 98801 | Wenatchee, WA | 14.6 mi |
| 98848 | Quincy, WA | 18.2 mi |
| 98823 | Ephrata, WA | 19.1 mi |
| 98836 | Monitor, WA | 19.2 mi |
| 98858 | Waterville, WA | 20.6 mi |
| 98815 | Cashmere, WA | 22.8 mi |
| 98843 | Orondo, WA | 23.3 mi |
| 98824 | George, WA | 24.2 mi |
| 98821 | Dryden, WA | 26.7 mi |
Questions about 98850
What is the ZIP+4 code for 98850?
98850 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 98850, you need to look up a specific street address to get them.
What city is 98850?
98850 is assigned to Rock Island, Washington, in Douglas 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.