ZIP Code 98645 — Silverlake, WA
98645 is a standard (street delivery) ZIP code serving Silverlake, Washington, in Cowlitz 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 98645 at a glance
| ZIP code | 98645 |
|---|---|
| Primary city | Silverlake |
| State | Washington (WA) |
| County | Cowlitz FIPS 53015 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Los_Angeles |
| Population | 2,216 |
| Coordinates | 46.325090, -122.779930 |
How ZIP+4 works in 98645
The four digits after the hyphen encode a delivery segment inside 98645. 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 98645 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 98645.
| ZIP | City | Distance |
|---|---|---|
| 98611 | Castle Rock, WA | 6.1 mi |
| 98591 | Toledo, WA | 8.2 mi |
| 98649 | Toutle, WA | 11.7 mi |
| 98626 | Kelso, WA | 11.9 mi |
| 98593 | Vader, WA | 12.3 mi |
| 98581 | Ryderwood, WA | 14 mi |
| 98542 | Ethel, WA | 14.3 mi |
| 98596 | Winlock, WA | 14.4 mi |
| 98582 | Salkum, WA | 15.1 mi |
| 98632 | Longview, WA | 15.8 mi |
| 98609 | Carrolls, WA | 18 mi |
| 98625 | Kalama, WA | 18.2 mi |
Questions about 98645
What is the ZIP+4 code for 98645?
98645 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 98645, you need to look up a specific street address to get them.
What city is 98645?
98645 is assigned to Silverlake, Washington, in Cowlitz 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.