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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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Northumberland County ZIP Codes

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

County State ZIP Code City Area Codes
Northumberland County PA 17834 Kulpmont 272, 570
Northumberland County PA 17836 Leck Kill 272, 570
Northumberland County PA 17840 Locust Gap 272, 570
Northumberland County PA 17847 Milton 272, 570
Northumberland County PA 17850 Montandon 272, 570
Northumberland County PA 17851 Mount Carmel 272, 570
Northumberland County PA 17857 Northumberland 272, 570
Northumberland County PA 17860 Paxinos 272, 570
Northumberland County PA 17865 Potts Grove 272, 570
Northumberland County PA 17866 Coal Township 272, 570
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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.