Sir John Thomas Buller Duckworth was the son of the naval commander Admiral John Thomas Duckworth by his second wife, a daughter of Bishop Buller of Exeter. He was born at Crediton in Devon in 1809 and educated at Eton and at Oriel College, Oxford, where he graduted B.A. in 1829. In 1817 he succeed his father as 2nd Baronet of Topsham in the County of Devon.

From 1845 to 1857 he was M.P. for Exeter. He was appointed Major of the 1st Devon yeomanry cavalry in 1844. His residences were 63, St James’s Street, London, and Wear House near Exeter in Devon.

He died, aged 78, on 29 November 1887 at Wear House near Exeter,