William Edward McManus (January 27, 1914 – March 3, 1997) was a 20th-century bishop of the Catholic Church in the United States. He served as auxiliary bishop of the Archdiocese of Chicago from 1967–1976 and bishop of the Diocese of Fort Wayne-South Bend in the state of Indiana from 1976-1985.
Born in Chicago, Illinois, McManus was ordained a priest on April 15, 1939 for the Archdiocese of Chicago by Cardinal George William Mundelein. On June 11, 1967 he was named Titular Bishop of Mesarfelta and Auxiliary Bishop of Chicago by Pope Paul VI. He was consecrated by Cardinal John Patrick Cody of Chicago. Bishops Cletus F. O'Donnell, of Madison and Aloysius John Wycislo, an auxiliary bishop of Chicago, were the principal co-consecrators. He served the archdiocese as a bishop for nine years until August 24, 1976 when Pope Paul VI named him the seventh bishop of Fort Wayne-South Bend. He was installed in Fort Wayne on October 29, 1976. Pope John Paul II accepted his resignation on February 18, 1985 after McManus had served the diocese as its bishop for nine years.