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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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Penobscot County ZIP Codes

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

County State ZIP Code City Area Codes
Penobscot County ME 04428 Eddington 207
Penobscot County ME 04429 Holden 207
Penobscot County ME 04430 East Millinocket 207
Penobscot County ME 04434 Etna 207
Penobscot County ME 04435 Exeter 207
Penobscot County ME 04444 Hampden 207
Penobscot County ME 04448 Howland 207
Penobscot County ME 04449 Hudson 207
Penobscot County ME 04450 Kenduskeag 207
Penobscot County ME 04451 Kingman 207
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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.