ZIP Code 98188 — Seattle, WA
98188 is a standard (street delivery) ZIP code serving Seattle, Washington, in King 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 98188 at a glance
| ZIP code | 98188 |
|---|---|
| Primary city | Seattle |
| State | Washington (WA) |
| County | King FIPS 53033 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Los_Angeles |
| Population | 27,311 |
| Coordinates | 47.447540, -122.273980 |
How ZIP+4 works in 98188
The four digits after the hyphen encode a delivery segment inside 98188. 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 98188 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.
Other ZIP codes in Seattle
Nearby ZIP codes
Showing the closest twelve. See every ZIP code within 25 miles of 98188.
| ZIP | City | Distance |
|---|---|---|
| 98158 | Seattle, WA | 1.6 mi |
| 98148 | Seattle, WA | 2.4 mi |
| 98057 | Renton, WA | 3 mi |
| 98168 | Seattle, WA | 3.1 mi |
| 98055 | Renton, WA | 3.4 mi |
| 98166 | Seattle, WA | 3.6 mi |
| 98178 | Seattle, WA | 3.8 mi |
| 98032 | Kent, WA | 3.9 mi |
| 98198 | Seattle, WA | 4 mi |
| 98031 | Kent, WA | 4.7 mi |
| 98146 | Seattle, WA | 5.3 mi |
| 98056 | Renton, WA | 6 mi |
Questions about 98188
What is the ZIP+4 code for 98188?
98188 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 98188, you need to look up a specific street address to get them.
What city is 98188?
98188 is assigned to Seattle, Washington, in King 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.