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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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Richland County ZIP Codes

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

County State ZIP Code City Area Codes
Richland County MT 59270 Sidney 306, 406, 474, 701
Richland County ND 58001 Abercrombie 218, 701
Richland County ND 58008 Barney 701
Richland County ND 58015 Christine 218, 701
Richland County ND 58018 Colfax 701
Richland County ND 58030 Fairmount 218, 605, 701
Richland County ND 58041 Hankinson 605, 701
Richland County ND 58053 Lidgerwood 605, 701
Richland County ND 58057 Mcleod 701
Richland County ND 58058 Mantador 701
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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.