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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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Fairfax County ZIP Codes

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

County State ZIP Code City Area Codes
Fairfax County VA 22303 Alexandria 571, 703
Fairfax County VA 22306 Alexandria 571, 703
Fairfax County VA 22307 Alexandria 571, 703
Fairfax County VA 22308 Alexandria 227, 240, 301, 571, 703
Fairfax County VA 22309 Alexandria 227, 240, 301, 571, 703
Fairfax County VA 22310 Alexandria 571, 703
Fairfax County VA 22312 Alexandria 571, 703
Fairfax County VA 22315 Alexandria 571, 703
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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.