| Name | What | Region | Country | Lat | Long | Elev ft. | Pop est |
|---|---|---|---|---|---|---|---|
| Union | city | Maine | United States | 44.21 | -69.27 | 32 | |
| Union Falls | city | Maine | United States | 43.57 | -70.56 | 114 | |
| Unionville | city | Maine | United States | 44.58 | -67.99 | 147 | |
| Unity | city | Maine | United States | 44.61 | -69.33 | 269 | |
| Upper Abbot | city | Maine | United States | 45.21 | -69.46 | 396 | |
| Upper Dam | city | Maine | United States | 44.88 | -70.86 | 1669 | |
| Upper Drew | city | Maine | United States | 45.63 | -68.07 | 830 | |
| Upper Frenchville | city | Maine | United States | 47.28 | -68.42 | 830 | |
| Upper Gloucester | city | Maine | United States | 43.99 | -70.29 | 364 | |
| Upper Landing | city | Maine | United States | 43.33 | -70.57 | 26 | |
| Upper Shirley Corner | city | Maine | United States | 45.38 | -69.60 | 1197 | |
| Upper Village (historical) | city | Maine | United States | 43.80 | -70.19 | 82 | |
| Upton | city | Maine | United States | 44.69 | -71.01 | 1797 |