| Country | Independence |
| Tanzania | 26 April 1964; Tanganyika became independent on 9 December 1961 (from UK-administered UN trusteeship); Zanzibar became independent on 19 December 1963 (from UK); Tanganyika united with Zanzibar on 26 April 1964 to form the United Republic of Tanganyika and Zanzibar; renamed United Republic of Tanzania on 29 October 1964 |
| Thailand | 1238 (traditional founding date; never colonized) |
| Timor-Leste | 28 November 1975 (independence proclaimed from Portugal); note - 20 May 2002 is the official date of international recognition of Timor-Leste's independence from Indonesia |
| Togo | 27 April 1960 (from French-administered UN trusteeship) |
| Tokelau | none (territory of New Zealand) |
| Tonga | 4 June 1970 (from UK protectorate) |
| Trinidad and Tobago | 31 August 1962 (from the UK) |
| Tunisia | 20 March 1956 (from France) |
| Turkey | 29 October 1923 (successor state to the Ottoman Empire) |
| Turkmenistan | 27 October 1991 (from the Soviet Union) |
| Turks and Caicos Islands | none (overseas territory of the UK) |
| Tuvalu | 1 October 1978 (from the UK) |
| Uganda | 9 October 1962 (from the UK) |
| Ukraine | 24 August 1991 (from the Soviet Union); notable earlier dates: ca. A.D. 982 (VOLODYMYR I consolidates Kyivan Rus), 1648 (establishment of Cossack Hetmanate) |
| United Arab Emirates | 2 December 1971 (from the UK) |