| Underwood, MN (City) |
| Unicoi, TN (Town) |
| Unicoi County, TN (County) |
| Union, AL (Town) |
| Union, NY (Town) |
| Union, IL (Village) |
| Union, IA (City) |
| Union, MN (Township) |
| Union, OH (City) |
| Union, SD (Township) |
| Union, SD (Township) |
| Union, SD (Township) |
| Union, SD (Township) |
| Union, SD (Township) |
| Union, SD (Township) |
