| Oshawa, MN (Township) |
| Oshkosh, MN (Township) |
| Oshkosh, WI (City) |
| Oshkosh, ND (Township) |
| Oshkosh, NE (City) |
| Oshkosh Town, WI (Town) |
| Oshtemo Township, MI (Township) |
| Oskaloosa, IA (City) |
| Oskaloosa, KS (City) |
| Oskaloosa, KS (Township) |
| Oskaloosa Township, IL (Township) |
| Oslo, MN (City) |
| Oslo, SD (Township) |
| Osloe, ND (Township) |
| Osmond, NE (Village) |
