• 1994: Became a member of Sikkim Democratic Front (SDF)
• 1994: Became first-time MLA from Chakung constituency of Sikkim Legislative Assembly
• 1994-1999: Served as Minister for Animal Husbandry, Ecclesiastical, and Industry Department in Sikkim government
• 1999: Became MLA from Chakung constituency of Sikkim Legislative Assembly
• 1999-2004: Served as Minister for Industries and Animal Husbandry in Sikkim government
• 2004: Became MLA from Chakung constituency of Sikkim Legislative Assembly
• 2004-2009: Served as Minister for Building and Housing Department
• 2009: Became MLA from Burtuk constituency of Sikkim Legislative Assembly
• 2009: Nominated as the Chairperson of Industries Department but did not serve
• 4 February 2013: Founded the Sikkim Krantikari Morcha (SKM)
• 6 September 2013: Resigned from SDF and became the president of the SKM
• 2014: Became MLA from Burtuk constituency of Sikkim Legislative Assembly
• 13 January 2017: Disqualified from the Sikkim Legislative Assembly
• 2017: Became the main opposition leader of Sikkim
• 2019: Became MLA from Poklok-Kamrang constituency of Sikkim Legislative Assembly
• 27 May 2019: Sworn in as the 6th Chief Minister of Sikkim
• 2024: Became MLA from Soreng–Chakung and Rhenock constituencies of Sikkim Legislative Assembly
• 2024: Became Sikkim CM for consecutive second time