| Locality | Post Code |
|---|---|
| Armington, Cascade | 59412 |
| Belt, Cascade | 59412 |
| Black Eagle, Cascade | 59414 |
| Cascade, Cascade | 59421 |
| Fort Shaw, Cascade | 59443 |
| Great Falls, Cascade | 59401, 59404, 59405 |
| Malmstrom Air Force Base, Cascade | 59402 |
| Monarch, Cascade | 59463 |
| Neihart, Cascade | 59465 |
| Sand Coulee, Cascade | 59472 |
| Simms, Cascade | 59477 |
| Stockett, Cascade | 59480 |
| Sun River, Cascade | 59483 |
| Tracy, Cascade | 59472 |
| Ulm, Cascade | 59485 |
| Vaughn, Cascade | 59487 |
| Wayne, Cascade | 59412 |