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U.S. ZIP Codes Database 2026

Search by ZIP code, city, county, or state and find clear postal details with maps, time zones, and area code data.

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Cowlitz County ZIP Codes

Browse all ZIP Codes, cities, and associated area codes registered in Cowlitz County.

County State ZIP Code City Area Codes
Cowlitz County WA 98581 Ryderwood 360, 564
Cowlitz County WA 98603 Ariel 360, 564
Cowlitz County WA 98609 Carrolls 360, 564
Cowlitz County WA 98611 Castle Rock 360, 564
Cowlitz County WA 98616 Cougar 360, 564
Cowlitz County WA 98625 Kalama 360, 503, 564, 971
Cowlitz County WA 98626 Kelso 360, 564
Cowlitz County WA 98632 Longview 360, 503, 564, 971
Cowlitz County WA 98645 Silverlake 360, 564
Cowlitz County WA 98649 Toutle 360, 564
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About U.S. ZIP Codes

ZIP codes are a United States Postal Service system introduced in 1963 to make mail routing more accurate and efficient. The standard format uses five digits, while ZIP+4 adds four more digits for a more precise delivery segment.

ZIP codes cover the United States, its territories, military mail routes, and other USPS delivery points. This directory organizes that data for practical lookup by ZIP code, city, county, and state.