William Augustus Banks III (b. March 11, 1956 at Travis Air Force Base, California) is an American athlete.

He was a track & field athlete competing in the triple jump. On June 16, 1985 he set a world record of 58 feet 11.5 inches at the national championships in Indianapolis, Indiana, USA.

He attended UCLA, and finished second in the NCAA Championships in 1977 and 1978.

He broke the American record in 1981.

He was a member of the 1980, 1984, and 1988 Olympic teams.

He participated on the 1983 and 1987 World Championship teams.

He was awarded the Track & Field News and United States Olympic Committee Athlete of the Year in 1985.

He served USA Track & Field as chair of the Athletes Advisory Committee in addition to serving as an organization vice president.

Banks will always be remembered as one of the most flamboyant athletes to compete in track and field. He is the originater of the now common hand clapping that takes place during many track and field events. His flamboyant personality was also present in his jumping. He has been reported as laughing during some of his jumps. He held the world record of 17.97 m until Jonathan Edwards broke it for the first time in 1995 with 17.98m.

He was inducted into the USA Track & Field Hall of Fame in 1999.