| Country | Capital |
| Tonga | name: Nuku'alofa geographic coordinates: 21 08 S, 175 12 W time difference: UTC+13 (18 hours ahead of Washington, DC during Standard Time) |
| Trinidad and Tobago | name: Port of Spain geographic coordinates: 10 39 N, 61 31 W time difference: UTC-4 (1 hour ahead of Washington, DC during Standard Time) |
| Tunisia | name: Tunis geographic coordinates: 36 48 N, 10 11 E time difference: UTC+1 (6 hours ahead of Washington, DC during Standard Time) |
| Turkey | name: Ankara geographic coordinates: 39 56 N, 32 52 E time difference: UTC+2 (7 hours ahead of Washington, DC during Standard Time) daylight saving time: +1hr, begins last Monday in March; ends last Sunday in October |
| Turkmenistan | name: Ashgabat (Ashkhabad) geographic coordinates: 37 57 N, 58 23 E time difference: UTC+5 (10 hours ahead of Washington, DC during Standard Time) |
| Turks and Caicos Islands | name: Grand Turk (Cockburn Town) geographic coordinates: 21 28 N, 71 08 W time difference: UTC-5 (same time as Washington, DC during Standard Time) daylight saving time: +1hr, begins second Sunday in March; ends first Sunday in November |
| Tuvalu | name: Funafuti geographic coordinates: 8 30 S, 179 12 E time difference: UTC+12 (17 hours ahead of Washington, DC during Standard Time) note: administrative offices are in Vaiaku Village on Fongafale Islet |
| Uganda | name: Kampala geographic coordinates: 0 19 N, 32 25 E time difference: UTC+3 (8 hours ahead of Washington, DC during Standard Time) |
| Ukraine | name: Kyiv (Kiev) note: pronounced KAY-yiv geographic coordinates: 50 26 N, 30 31 E time difference: UTC+2 (7 hours ahead of Washington, DC during Standard Time) daylight saving time: +1hr, begins last Sunday in March; ends last Sunday in October |
| United Arab Emirates | name: Abu Dhabi geographic coordinates: 24 28 N, 54 22 E time difference: UTC+4 (9 hours ahead of Washington, DC during Standard Time) |
| United Kingdom | name: London geographic coordinates: 51 30 N, 0 10 W time difference: UTC 0 (5 hours ahead of Washington, DC during Standard Time) daylight saving time: +1hr, begins last Sunday in March; ends last Sunday in October note: applies to the United Kingdom proper, not to its overseas dependencies or territories |