William Payne Whitney was an American businessman and member of the influential Whitney family. He inherited a fortune and enlarged it through business dealings, then devoted much of his money and efforts to a wide variety of philanthropic purposes. His will included funds to expand the New York Hospital, now called NewYork-Presbyterian Hospital, where the Payne Whitney Psychiatric Clinic was established.

The Whitney family is a prominent American family descended from English immigrant John Whitney (1592–1673), who left London in 1635 and settled in Watertown, Massachusetts. The historic family mansion in Watertown, known as The Elms, was built for the Whitneys in 1710. The Whitneys today occupy a distinguished position in American society as a result of their entrepreneurship, wealth, and philanthropy. They are also members of the Episcopal Church.