Born on 16 July 1723 in Plympton, Devon, the son of a schoolmaster. He studied with T.Hudson in London 1740-3 and practised as a portrait painter in London and the West Country before sailing to Italy in 1749. He stayed principally in Rome, but also visited Florence, Bologna and Venice before returning to London in 1753. The visit was crucial to his development; throughout his life he recalled the Sistine Chapel decorations, the sculptors of antiquity, the Bolognese seventeenth-century classicists and the Venetian sixteenth-century painters.

He became increasingly successful in London, and his friendships with Garrick, Burke, Goldsmith and Johnson were both warm and shrewd. He exhibited at the SA 1760-8 and in 1768 was elected the first President of the Royal Academy, London, where between 1769 and 1790 he exhibited 244 pictures (of which 32 were not portraits). He was knighted in 1769.

In 1784 Reynolds succeeded Ramsay as Principal Painter to the King, but his Royal portraits were not a success. He ceased to paint, because of failing eye-sight, in the summer of 1789 and he died in London on 23 February 1792.

He was buried with great pomp in St. Paul's Cathedral.