| U S A F Academy, Colorado | 80840 | More |
| U S A F Academy, Colorado | 80841 | More |
| Ubly, Michigan | 48475 | More |
| Ucon, Idaho | 83454 | More |
| Udall, Missouri | 65766 | More |
| Udall, Kansas | 67146 | More |
| Udell, Iowa | 52593 | More |
| Uehling, Nebraska | 68063 | More |
| Uhrichsville, Ohio | 44683 | More |
| Ukiah, California | 95482 | More |
| Ukiah, Oregon | 97880 | More |
| Uledi, Pennsylvania | 15484 | More |
| Ulen, Minnesota | 56585 | More |
| Ullin, Illinois | 62992 | More |
| Ulm, Montana | 59485 | More |
| Ulm, Arkansas | 72170 | More |
| Ulman, Missouri | 65083 | More |
| Ulmer, South Carolina | 29849 | More |
| Ulster, Pennsylvania | 18850 | More |
| Ulster Park, New York | 12487 | More |
| Ulysses, Pennsylvania | 16948 | More |
| Ulysses, Kentucky | 41264 | More |
| Ulysses, Kansas | 67880 | More |
| Ulysses, Nebraska | 68669 | More |
| Umatac, Guam | 96918 | More |
| Umatilla, Florida | 32784 | More |
| Umatilla, Oregon | 97882 | More |
| Umbarger, Texas | 79091 | More |
| Umpire, Arkansas | 71971 | More |
| Umpqua, Oregon | 97486 | More |
| Una, South Carolina | 29378 | More |
| Unadilla, New York | 13849 | More |
| Unadilla, Georgia | 31091 | More |
| Unadilla, Nebraska | 68454 | More |
| Unalakleet, Alaska | 99684 | More |
| Unalaska, Alaska | 99685 | More |
| Uncasville, Connecticut | 06382 | More |
| Uncle Sam, Louisiana | 70792 | More |
| Underhill, Vermont | 05489 | More |
| Underhill Center, Vermont | 05490 | More |
| Underwood, Indiana | 47177 | More |
| Underwood, Iowa | 51576 | More |
| Underwood, Minnesota | 56586 | More |
| Underwood, North Dakota | 58576 | More |
| Underwood, Washington | 98651 | More |
| Uneeda, West Virginia | 25205 | More |
| Unicoi, Tennessee | 37692 | More |
| Union, New Hampshire | 03887 | More |
| Union, Maine | 04862 | More |
| Union, New Jersey | 07083 | More |
