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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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Colusa County ZIP Codes

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

County State ZIP Code City Area Codes
Colusa County CA 95912 Arbuckle 530
Colusa County CA 95932 Colusa 530
Colusa County CA 95950 Grimes 530
Colusa County CA 95955 Maxwell 530
Colusa County CA 95970 Princeton 530
Colusa County CA 95979 Stonyford 530, 707
Colusa County CA 95987 Williams 530, 707

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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.