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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 20159 Hamilton 540
Loudoun County VA 20160 Lincoln 540
Loudoun County VA 20163 Sterling 571, 703
Loudoun County VA 20164 Sterling 571, 703
Loudoun County VA 20165 Sterling 227, 240, 301, 571, 703
Loudoun County VA 20166 Sterling 571, 703
Loudoun County VA 20167 Sterling 571
Loudoun County VA 20175 Leesburg 540, 571, 703, 826
Loudoun County VA 20176 Leesburg 227, 240, 301, 540, 571, 703, 826
Loudoun County VA 20177 Leesburg 571
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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.