In 1866 he was elected an Associate of the Royal Academy, and in 1874 received full academical honours in succession to Sir Edwin Landseer. His diploma picture was "Jacobites, 1745". Pettie was a hard and rapid worker, and, in his best days, a colourist of a high order and a brilliant executant. In his early days he produced a certain amount of book illustration. His connection with Good Words began in 1861, and was continued until 1864. He painted a portrait of the painter James Campbell Noble RSA and this is exhibited in the Scottish National Portrait Gallery in Edinburgh. In 1894 a selection of his work was included in the Winter Exhibition of the Royal Academy. His self-portrait is in the Tate Gallery.