The Telangana supporters danced in the streets, burst crackers, splashed gulal (colours), and distributed sweets in Hyderabad, Warangal, Karimnagar and other towns.
Throngs of people visited the Telangana martyrs memorial here.
TRS, which was in the forefront of separate statehood agitation, had made arrangements at its office here for celebrations as activists gathered.
Telangana is set to become the 29th state of the Union with Parliament approving the historic bill to carve the new state out of Andhra Pradesh amid vociferous protests by members from Seemandhra region as also from Trinamool Congress and Shiv Sena.
The suspense over the passage of the Andhra Pradesh Reorganisation Bill, 2014 came to an end with BJP eventually backing the government.