William Anthony Jackowski (September 27, 1914 - July 29, 1996) was a professional baseball umpire who worked in the National League from 1952 to 1968. Jackowski umpired 2,517 major league games in his 17 year career. He umpired in three World Series (1958, 1960 and 1966) and three All-Star Games (1956, 1959 and 1963).