William or Bill Mayer may refer to:
Bill Mayer (born 1951), American illustrator William Mayer (composer) (1925–2017), American composer William A. Mayer (f. 1956–1959), American polo player William Daniel Mayer (1941–2026), former member of the Maryland House of Delegates William E. Mayer, investment banker and former owner of the Hartford Colonials William V. Mayer (1920–1989), American biologist and educator
See also William Meyer (disambiguation) William Moyer (1933–2002), author and organizer in the 1966 Chicago Freedom Movement