William Collins RA (8 September 1788 in London – 17 February 1847 in London) was an English landscape and genre painter. In the late 19th century his work was more popular and highly valued than even that of J M W Turner or John Constable.
Collins was born in Great Titchfield Street, London, son of William Collins Sr., an Irish-born picture-dealer and writer. He showed a great aptitude for art from an early age, and was, for a while, an informal pupil of George Morland. In 1807, he entered the schools of the Royal Academy (at the same time as William Etty), and exhibited at the Academy for the first time in the same year. In 1809 he was awarded a medal in the life school, and exhibited three pictures - Boy at Breakfast, Boys with a Bird's-nest and a Portrait of Master Lee as he spoke the Prologue at the Haymarket Theatre.
In 1811, Collins sold a picture entitled The Young Fifer, to the Marquis of Stafford for 80 guineas, and the next year produced the work which made him famous, The Sale of the Pet Lamb, which was sold for 140 forty guineas and engraved by S. W. Reynolds. He now became the chief support of his family - following the death of his father (in financial difficulty) in that year - and found some valuable patrons, especially Sir Thomas Freeman Heathcote, Sir John Leicester, Sir Robert Peel, Sir George Beaumont, and Lord Liverpool. In 1814 two pictures, The Blackberry Gatherers and The Birdcatchers (both sold privately), won him an associateship of the Royal Academy (ARA).