9 cities
| City | County | 2025 Pop. ↓ |
|---|---|---|
| Joliet | Carbon County | 629 |
| Jefferson City | Jefferson County | 482 |
| Jordan | Garfield County | 358 |
| Joplin | Liberty County | 287 |
| Jette | Lake County | 177 |
| Judith Gap | Wheatland County | 107 |
| Jeffers | Madison County | 56 |
| Jardine | Park County | 54 |
| Jackson | Beaverhead County | 20 |