William Bonnell (February 1, 1804 – October 12, 1865) was an American portrait painter. His works are generally placed in the folk art category, due to his nonexistence of formal training.
Born in Clinton, New Jersey, Bonnell was the second son of Colonel Clement Bonnell (1766-1836) and Rachel Wolverton. His grandfather was the Revolutionary War Colonel Abraham Bonnell (1732-1797), the commissioner of a tavern that was one of the first recruiting places for minutemen in that area. He married Margaret Hinchman (1813-1901) in 1836.
As of now, only twenty paintings of his are known to exist, most inscribed as soon as his proclaim and a date upon the reverse. An unidentified painting of a hunting dog once the unlikely reveal of "Chustetunk's Frosty Ferris" may be his first canvas. His first signed and old works are from 1823. Traditionally, a sign that was originally in Hampton at the Perryville Inn, with Andrew Jackson and an American flag, is endorsed to him, but he was not known as a sign painter. Most of his works date from c.1825, when he painted the likenesses of several Hunterdon County residents.
Only one painting from external New Jersey is attested to; showing Andrew and Eliza Everhart Yerkes; farmers in Warminster, Pennsylvania. No works after c.1835 have been discovered. His dexterity shows a determined improvement beyond the course of his career; including the supplement of background landscapes.
Some of his works may be seen at the Art Institute of Chicago. The sign is at the Hunterdon County Historical Association in Flemington.