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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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Monroe County ZIP Codes

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

County State ZIP Code City Area Codes
Monroe County FL 33036 Islamorada 305, 786
Monroe County FL 33037 Key Largo 305, 786
Monroe County FL 33040 Key West 305, 786
Monroe County FL 33041 Key West 305
Monroe County FL 33042 Summerland Key 305, 786
Monroe County FL 33043 Big Pine Key 305, 786
Monroe County FL 33045 Key West 305
Monroe County FL 33050 Marathon 305, 786
Monroe County FL 33051 Key Colony Beach 305, 786
Monroe County FL 33052 Marathon Shores 305, 786
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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.