Taking an MA from Presidency College, then under the University of Calcutta, in 1895, he entered government service the following year.
[4] He was appointed a Companion of the Order of the Indian Empire (CIE) in the 1913 King's Birthday Honours,[5] and was promoted to acting Deputy Secretary in the Finance Department in 1915.
[6] On 8 January 1919, he was promoted to Commander of the Order of the British Empire, Civil Division (CBE), for his services to the war effort;[7] later the same year, he was appointed Military Accountant-General.
[11] In 1931, Mitra was appointed as the third Indian High Commissioner in the United Kingdom, succeeding Sir Atul Chandra Chatterjee.
Mitra was succeeded as High Commissioner in 1936 by Sir Feroz Khan Noon, and died on 25 February of the following year, aged 61.