Tirath Singh Thakur enrolled as a pleader in October 1972 and joined the chamber of his father Late Shri Devi Das Thakur, former governor of Assam a leading advocate and later, a judge of High Court of J & K. Justice T. S. Thakur practised in civil, criminal, constitutional, taxation and service matters in the High Court of Jammu & Kashmir.

[citation needed] He was appointed acting chief justice of the Delhi High Court on 9 April 2008 and took over as the chief justice of the High Court of Punjab and Haryana on 11 August 2008.

He was elevated as a judge of the Supreme Court and assumed charge on 17 November 2009.

[1] He was appointed Chief Justice of India on 18 November 2015 assuming office on 3 December 2015,[2] succeeding Justice H. L. Dattu who retired as CJI on 2 December 2015, on turning 65 years of age.

[3] In April 2016, he lamented the inaction by the government in increasing the number of judges.