Kennewick Washington ZIP Codes

Kennewick holds 3 ZIP codes, all inside one county and one postal prefix.

Every ZIP code in Kennewick

The complete list of Kennewick, Washington ZIP codes with the county each falls in.
ZIP code	County
99336	Benton County
99337	Benton County
99338	Benton County

We do not publish a delivery type (standard, PO box, unique) or a neighbourhood for each ZIP. USPS delivery-type products are licensed, and no clean-rights source maps ZIP codes to neighbourhoods — so the Kennewick codes above are listed without a column we would have to invent.

Scope every ZIP code recorded for Kennewick. Source GeoNames US postal codes (2026-07 postal dump) and Census 2024 county Gazetteer (2024 Gazetteer). Updated 15 July 2026. ZIP codes are delivery-route groupings, not areas; the boundaries implied by any ZIP map are approximations.

How these codes cluster

Every Kennewick ZIP code begins 993. Those first three digits identify the sectional center facility that processes mail for this part of Washington. Statewide that range covers 36 ZIP codes, so Kennewick accounts for 8% of it.

Every Washington ZIP prefix and the region it covers →

Area codes covering Kennewick

ZIP codes and area codes are separate systems — one routes mail, the other routes calls — and they do not share boundaries. The code below serves the same ground Kennewick occupies.

509 Area code 509

Kennewick Washington area codes in full →

Where Kennewick's ZIP codes sit

Each point is one Kennewick ZIP code, plotted from its record coordinates. The outline is the convex envelope of those points — a footprint, not a boundary.

Reference points and footprint
Not an official NANPA boundary
Not a USPS delivery area

Cities near Kennewick

The closest places to Kennewick with their own ZIP code list, nearest first.
City	Distance	ZIP codes
Pasco Washington ZIP codes	5.4 mi	2 ZIP codes
Richland Washington ZIP codes	8.4 mi	2 ZIP codes
West Richland Washington ZIP codes	13 mi	1 ZIP code
Benton City Washington ZIP codes	15 mi	1 ZIP code
Mesa Washington ZIP codes	27 mi	1 ZIP code
Prosser Washington ZIP codes	28 mi	1 ZIP code
Grandview Washington ZIP codes	35 mi	1 ZIP code
Connell Washington ZIP codes	36 mi	1 ZIP code

Straight-line distance between place reference points, not driving distance.