The only son of James Paine the elder, he studied at the Saint Martin"s Lane Academy. He also had access to the Richmond House classical collection, opened to the Society of Artists of Great Britain by his father"s efforts, from 1770. His father, by his will dated February 1786, probably left his son financially independent.
Paine appears to have travelled in Italy. In 1788 he had residences in both North End, Hammersmith, and Salisbury Street. On 12 March 1830 Christie sold the pictures, casts, books of architecture, and other items "the property of J. Paine, Esq., Architect (deceased)".
They went to Sir John Soane"s Museum.
A large volume with "J. Paine, jun. Architect Rome, 1774", on the outside, containing 57 drawings of studies at Rome, all signed by him (plans of four palaces, views at Albano and Tivoli, measured drawings of the Ponte Rotto, and a number of statues with their measurements), went in time to the South Kensington Museum.
In 1791 he was one of the original fifteen members of the Architects" Club.
