Tokelau:
1 April - 31 March
Tonga:
1 July - 30 June
Trinidad and Tobago:
1 October - 30 September
Tunisia:
calendar year
Turkey:
calendar year
Turkmenistan:
calendar year
Turks and Caicos Islands:
calendar year
Tuvalu:
calendar year
Uganda:
1 July - 30 June
Ukraine:
calendar year