As of March 2020[update], nine people from the CPI(M) have held the position of a chief minister — four in Kerala, three in Tripura, and two in West Bengal, out of which only one — Pinarayi Vijayan is incumbent.
West Bengal: Official website of West Bengal Legislative Assembly[4]
Tripura: Legislative Bodies in India (an Indian government website) page on Tripura Legislative Assembly[5] and a news article for the date of end of Manik Sarkar's term.[6]
^Namboodiripad has served two terms as a chief minister; the first in 1957 as a CPI leader and second in 1967 as a CPI(M) leader.[7]
^Basu, Durga Das (2011) [1st pub. 1960]. Introduction to the Constitution of India (20th ed.). LexisNexis Butterworths Wadhwa Nagpur. pp. 241–245. ISBN978-81-8038-559-9. Note: although the text talks about Indian state governments in general, it applies for the specific case of Chhattisgarh as well.
^"Chief Ministers". Kerala Legislature. Archived from the original on 8 August 2019. Retrieved 8 August 2019.
^"Premiers and Chief Ministers of West Bengal". West Bengal Legislative Assembly. Archived from the original on 12 March 2016. Retrieved 24 August 2018. Note: The website link may not work as it has few glitches; only the archive link works. Also, the source has few errors regarding the tenure of Ajoy Kumar Mukherjee; the correct dates are provided in the "Origin and Growth" section of the given website.
^Krishnakumar, R. (4 April 1998). "Farewell to EMS". Frontline. Thiruvananthapuram. Archived from the original on 6 August 2019. Retrieved 11 August 2019.