ZIP Code 99346

99346 is one of Washington's ZIP codes, delivering to addresses in Plymouth, Benton County.

City: Plymouth
County: Benton County
State: Washington
Prefix: 993xx

Where this code sits

99346 is part of the 993xx range, the group of codes handled by one mail processing centre. It is the only ZIP code delivering to Plymouth.

Area codes over the same ground

Postal and telephone geography are drawn separately, so these codes cover the area 99346 delivers to without sharing its boundary.

509 Area code 509

ZIP codes nearest 99346

The ZIP codes whose reference points sit closest to 99346.
ZIP code	Distance	Delivers to
ZIP code 97882	3.1 mi	Umatilla, OR
ZIP code 97844	5.8 mi	Irrigon, OR
ZIP code 97838	8.2 mi	Hermiston, OR
ZIP code 97875	14 mi	Stanfield, OR
ZIP code 97826	16 mi	Echo, OR
ZIP code 97818	17 mi	Boardman, OR
ZIP code 99338	17 mi	Kennewick, WA
ZIP code 99345	18 mi	Paterson, WA

Straight-line distance between place reference points, not driving distance. Where a place has no Census Gazetteer point, its postal centroid is used instead.

Each point is the reference point for 99346, plotted from its record coordinates.

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

Scope ZIP code 99346. Source GeoNames US postal codes (2026-07 postal dump) and Census 2024 county Gazetteer (2024 Gazetteer). Updated 15 July 2026. A ZIP code is a set of delivery routes, not an area; the point shown is a record coordinate, not a centre.