County ZIP codes · North Dakota · FIPS 38017
Cass County, ND ZIP Codes
Cass County, North Dakota has 39 ZIP codes (Census 2020 ZCTA-county file; GeoNames postal codes, October 2026): 30 residential and 9 for PO boxes or a single organization. 25 of the residential ones lie mainly in Cass County and 5 mainly in a neighboring county; 12 cross the county line. Median household income ranges from $58,801 in 58103 (Fargo) to $142,361 in 58047 (Horace) (Census Bureau, ACS 2020-2024).
- ACS2020-24
- Census2020
Where are the ZIP codes of Cass County?
Source: U.S. Census Bureau, 2020 ZCTA cartographic boundaries; ACS 2020-2024 5-year estimates (B19013).
How different are its ZIP codes?
The middle half of its ranked ZIP codes (1,000+ people living in households) report median household incomes between $59,533 and $107,396.
They carry 27 postal town names.
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B19013).
All 30 residential ZIP codes in Cass County
25 ZIP codes lie mainly in Cass County; 5 more reach into it from a neighboring county and follow the first table.
| In this county | ||||||
|---|---|---|---|---|---|---|
| 58104 | Fargo | 49,168 | 1,753 | $86k | $359k | 100% |
| 58103 | Fargo | 48,796 | 4,260 | $59k | $242k | 100% |
| 58078 | West Fargo | 40,631 | 1,020 | $91k | $324k | 100% |
| 58102 | Fargo | 32,912 | 1,040 | $60k | $242k | 100% |
| 58047 | Horace | 5,636 | 80 | $142k | $432k | 97% |
| 58012 | Casselton | 3,049 | 42 | $75k | $284k | 100% |
| 58105 | Fargo | 2,825 | 11,870 | $124k | – | 100% |
| 58051 | Kindred | 1,980 | 18 | $107k | $331k | 59% |
| 58059 | Mapleton | 1,670 | 15 | $116k | $332k | 100% |
| 58042 | Harwood | 1,344 | 31 | $138k | $347k | 100% |
| 58005 | Argusville | 898 | 9 | $143k | $357k | 100% |
| 58021 | Davenport | 584 | 9 | $109k | $245k | 100% |
| 58006 | Arthur | 573 | 12 | $95k | $261k | 100% |
| 58052 | Leonard | 529 | 3 | $88k | $254k | 56% |
| 58048 | Hunter | 505 | 4 | $100k | $175k | 76% |
| 58079 | Wheatland | 504 | 4 | $127k | $350k | 100% |
| 58071 | Tower City | 486 | 5 | $109k | $194k | 56% |
| 58011 | Buffalo | 449 | 4 | $100k | $245k | 100% |
| 58036 | Gardner | 360 | 4 | $101k | $292k | 100% |
| 58064 | Page | 332 | 2 | $76k | $223k | 74% |
| 58031 | Fingal | 301 | 2 | $57k | $71k | 54% |
| 58004 | Amenia | 241 | 5 | $72k | $208k | 100% |
| 58029 | Erie | 88 | 2 | $146k | $400k | 100% |
| 58007 | Ayr | 81 | 2 | $81k | $169k | 100% |
| 58002 | Absaraka | 17 | 5 | – | – | 100% |
Partly in Cass County
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates; county shares by land area (Census 2020 ZCTA-county relationship file).
Which ZIP codes cross the county line?
12 ZIP codes of Cass County extend into another county. A ZIP code follows mail routes, not county borders.
| ZIP | In Cass | Elsewhere |
|---|---|---|
| 58047 | 97% | Richland County 3% |
| 58051 | 59% | Richland County 41% |
| 58027 | 41% | Ransom County 45%; Barnes County 14% |
| 58046 | 2% | Steele County 85%; Barnes County 13% |
| 58052 | 56% | Richland County 33%; Ransom County 11% |
| 58048 | 76% | Traill County 24% |
| 58071 | 56% | Barnes County 44% |
| 58064 | 74% | Barnes County 24%; Steele County 2% |
| 58031 | 54% | Barnes County 46% |
| 58035 | 34% | Traill County 42%; Steele County 24% |
| 58038 | 40% | Traill County 60% |
| 58068 | 2% | Ransom County 98% |
Source: U.S. Census Bureau, 2020 ZCTA-county relationship file (shares of land area).
PO Box and single-organization ZIP codes
Source: GeoNames postal codes (CC BY 4.0).
Which first three digits do Cass County's ZIP codes use?
The first three digits of a ZIP code name the sectional center, the mail processing plant that sorts it. Cass County's ZIP codes use 2 prefixes: 580 and 581.
Source: U.S. Postal Service, labeling list L005 (3-digit ZIP Code prefix groups, SCF sortation), effective October 1, 2026.