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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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Mercer County ZIP Codes

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

County State ZIP Code City Area Codes
Mercer County ND 58580 Zap 701
Mercer County NJ 08512 Cranbury 609, 640, 732, 848
Mercer County NJ 08520 Hightstown 609, 640, 732, 848
Mercer County NJ 08525 Hopewell 609, 640, 908
Mercer County NJ 08534 Pennington 609, 640
Mercer County NJ 08540 Princeton 609, 640, 732, 848, 908
Mercer County NJ 08541 Princeton 609
Mercer County NJ 08542 Princeton 609, 640
Mercer County NJ 08543 Princeton 609
Mercer County NJ 08544 Princeton 609, 640
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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.