| Locality | Post Code |
|---|---|
| Arpan, Butte | 57762 |
| Belle Fourche, Butte | 57717 |
| Castle Rock, Butte | 57760 |
| Cedar Canyon, Butte | 57760 |
| Fruitdale, Butte | 57717 |
| Gill, Butte | 57760 |
| Hoover, Butte | 57760 |
| Mason, Butte | 57717 |
| Newell, Butte | 57760 |
| Nisland, Butte | 57762 |
| Vale, Butte | 57788 |
| Willet, Butte | 57717 |