County ZIP codes · Montana · FIPS 30013
Cascade County, MT ZIP Codes
Cascade County, Montana has 20 ZIP codes (Census 2020 ZCTA-county file; GeoNames postal codes, October 2026): 17 residential and 3 for PO boxes or a single organization. 15 of the residential ones lie mainly in Cascade County and 2 mainly in a neighboring county; 9 cross the county line. Median household income ranges from $55,299 in 59401 to $83,867 in 59404 (Census Bureau, ACS 2020-2024).
- ACS2020-24
- Census2020
Where are the ZIP codes of Cascade 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 $55,299 and $82,955.
They carry 15 postal town names.
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B19013).
All 17 residential ZIP codes in Cascade County
15 ZIP codes lie mainly in Cascade County; 2 more reach into it from a neighboring county and follow the first table.
| In this county | ||||||
|---|---|---|---|---|---|---|
| 59405 | Great Falls | 33,350 | 70 | $59k | $250k | 99% |
| 59404 | Great Falls | 28,822 | 87 | $84k | $296k | 72% |
| 59401 | Great Falls | 13,255 | 4,478 | $55k | $223k | 100% |
| 59421 | Cascade | 2,069 | 3 | $78k | $378k | 96% |
| 59412 | Belt | 1,685 | 4 | $83k | $251k | 97% |
| 59487 | Vaughn | 1,548 | 28 | $56k | $229k | 92% |
| 59414 | Black Eagle | 781 | 448 | $70k | $190k | 100% |
| 59485 | Ulm | 772 | 14 | $90k | $322k | 100% |
| 59443 | Fort Shaw | 705 | 12 | $81k | $271k | 93% |
| 59472 | Sand Coulee | 507 | 9 | $68k | $235k | 100% |
| 59477 | Simms | 334 | 5 | $42k | $238k | 100% |
| 59480 | Stockett | 328 | 2 | $81k | $280k | 100% |
| 59483 | Sun River | 247 | 3 | $98k | $429k | 100% |
| 59463 | Monarch | 142 | 1 | – | $345k | 94% |
| 59465 | Neihart | 39 | 0 | $83k | $227k | 100% |
Partly in Cascade 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?
9 ZIP codes of Cascade County extend into another county. A ZIP code follows mail routes, not county borders.
| ZIP | In Cascade | Elsewhere |
|---|---|---|
| 59405 | 99% | Chouteau County 1% |
| 59404 | 72% | Chouteau County 28% |
| 59421 | 96% | Lewis and Clark County 4% |
| 59412 | 97% | Judith Basin County 3% |
| 59487 | 92% | Teton County 8% |
| 59468 | 29% | Teton County 71% |
| 59443 | 93% | Teton County 7% |
| 59440 | 32% | Chouteau County 68% |
| 59463 | 94% | Judith Basin County 6% |
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 Cascade County's ZIP codes use?
The first three digits of a ZIP code name the sectional center, the mail processing plant that sorts it. Every ZIP code of Cascade County starts with 594.
| Prefix | Sectional center | Here | All codes |
|---|---|---|---|
| 594 | Great Falls, MT (SCF 594) | 20 | 64 |
Source: U.S. Postal Service, labeling list L005 (3-digit ZIP Code prefix groups, SCF sortation), effective October 1, 2026.