William Plankinton, American businessman, industrialist and banker (b. 1843)
William Plankinton (November 7, 1843 – March 29, 1905) was an American businessman, manufacturer, and industrialist. He followed in his father's footsteps in the meat packing and meat processing industry.

Plankinton was associated with the Milwaukee museum, public library, industrial exposition and Chamber of Commerce. As a businessman he was a banker. He was implicated in a scandal of fraud and embezzlement, for which he was sued.