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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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New Haven County ZIP Codes

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

County State ZIP Code City Area Codes
New Haven County CT 06721 Waterbury 203
New Haven County CT 06722 Waterbury 203
New Haven County CT 06723 Waterbury 203
New Haven County CT 06724 Waterbury 203
New Haven County CT 06725 Waterbury 203
New Haven County CT 06726 Waterbury 203
New Haven County CT 06749 Waterbury 203
New Haven County CT 06762 Middlebury 203, 475, 860, 959
New Haven County CT 06770 Naugatuck 203, 475
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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.