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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 59401 Great Falls 406
Cascade County MT 59402 Malmstrom AFB 406
Cascade County MT 59403 Great Falls 406
Cascade County MT 59404 Great Falls 406
Cascade County MT 59405 Great Falls 406
Cascade County MT 59406 Great Falls 406
Cascade County MT 59412 Belt 406
Cascade County MT 59414 Black Eagle 406
Cascade County MT 59421 Cascade 406
Cascade County MT 59443 Fort Shaw 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.