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U.S. ZIP Codes Database 2026

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Loudoun County ZIP Codes

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

County State ZIP Code City Area Codes
Loudoun County VA 20101 Dulles 571
Loudoun County VA 20102 Dulles 571
Loudoun County VA 20103 Dulles 571
Loudoun County VA 20104 Dulles 571
Loudoun County VA 20105 Aldie 540, 571, 703, 826
Loudoun County VA 20107 Arcola 571, 703
Loudoun County VA 20117 Middleburg 540, 571, 703, 826
Loudoun County VA 20118 Middleburg 540
Loudoun County VA 20129 Paeonian Springs 540, 571, 703, 826
Loudoun County VA 20131 Philomont 540, 826
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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.