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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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Somerset County ZIP Codes

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

County State ZIP Code City Area Codes
Somerset County NJ 08528 Kingston 609, 640, 732, 848
Somerset County NJ 08553 Rocky Hill 609, 640, 908
Somerset County NJ 08558 Skillman 609, 640, 908
Somerset County NJ 08805 Bound Brook 732, 848
Somerset County NJ 08807 Bridgewater 732, 848, 908
Somerset County NJ 08821 Flagtown 908
Somerset County NJ 08823 Franklin Park 732, 848, 908
Somerset County NJ 08835 Manville 732, 848, 908
Somerset County NJ 08836 Martinsville 732, 848, 908
Somerset County NJ 08844 Hillsborough 609, 640, 732, 848, 908
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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.