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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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San Mateo County ZIP Codes

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

County State ZIP Code City Area Codes
San Mateo County CA 94044 Pacifica 650
San Mateo County CA 94060 Pescadero 650, 831
San Mateo County CA 94061 Redwood City 650
San Mateo County CA 94062 Redwood City 650
San Mateo County CA 94063 Redwood City 650
San Mateo County CA 94064 Redwood City 650
San Mateo County CA 94065 Redwood City 650
San Mateo County CA 94066 San Bruno 650
San Mateo County CA 94070 San Carlos 650
San Mateo County CA 94074 San Gregorio 650
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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.