William Edward Haller (born February 28, 1935 in Joliet, Illinois) is a retired Major League Baseball umpire. Haller officiated 3,068 regular season games in the American League in 1961 and from 1963 to 1982. He also worked 15 American League Championship Series games in four series (1970, 1973, 1976 and 1980), 27 World Series contests in four different years (1968, 1972, 1978 and 1982) and four All-Star games (1963, 1970, 1975 and 1981).