<P> In the Republic of India, a chief minister is the head of government of each of twenty - nine states and two union territories (Delhi and Puducherry). According to the Constitution of India, at the state - level, the governor is de jure head, but de facto executive authority rests with the chief minister . Following elections to the state legislative assembly, the governor usually invites the party (or coalition) with a majority of seats to form the government . The governor appoints the chief minister, whose council of ministers are collectively responsible to the assembly . Given he has the assembly's confidence, the chief minister's term is usually for a maximum of five years; there are no limits to the number of terms he / she can serve . </P> <P> Of the thirty - one incumbents, three are women--Mamata Banerjee in West Bengal, Mehbooba Mufti in Jammu and Kashmir, and Vasundhara Raje in Rajasthan . Serving since December 1994 (for 7003831700000000000 ♠ 22 years, 281 days), Sikkim's Pawan Kumar Chamling has the longest incumbency . Virbhadra Singh (b . 1934) of Himachal Pradesh is the oldest chief minister, while Arunachal Pradesh's Pema Khandu (b . 1979) is the youngest . Thirteen incumbents belong to the Bharatiya Janata Party, six to the Indian National Congress and two to the Communist Party of India (Marxist); no other party has more than one chief minister in office . </P> <Table> <Tr> <Th> Colour key for parties </Th> </Tr> <Tr> <Td> Aam Aadmi Party All India Anna Dravida Munnetra Kazhagam All India Trinamool Congress Bharatiya Janata Party Biju Janata Dal Communist Party of India (Marxist) Indian National Congress Jammu and Kashmir Peoples Democratic Party Janata Dal (United) Naga People's Front Sikkim Democratic Front Telangana Rashtra Samithi Telugu Desam Party </Td> </Tr> </Table> <Tr> <Th> Colour key for parties </Th> </Tr>

List of union territories of india and their chief ministers