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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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Cascade County ZIP Codes

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

County State ZIP Code City Area Codes
Cascade County MT 59463 Monarch 406
Cascade County MT 59465 Neihart 406
Cascade County MT 59472 Sand Coulee 406
Cascade County MT 59477 Simms 406
Cascade County MT 59480 Stockett 406
Cascade County MT 59483 Sun River 406
Cascade County MT 59485 Ulm 406
Cascade County MT 59487 Vaughn 406
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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.