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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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Fremont County ZIP Codes

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

County State ZIP Code City Area Codes
Fremont County ID 83420 Ashton 208, 307, 986
Fremont County ID 83421 Chester 208, 986
Fremont County ID 83429 Island Park 208, 406, 986
Fremont County ID 83433 Macks Inn 208, 986
Fremont County ID 83436 Newdale 208, 986
Fremont County ID 83438 Parker 208, 986
Fremont County ID 83445 Saint Anthony 208, 986
Fremont County ID 83451 Teton 208, 986
Fremont County WY 82310 Jeffrey City 307
Fremont County WY 82501 Riverton 307
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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.