He was preceded in death by his first wife, Catherine Richey Flannery; his son, Richard Waring Flannery and his daughter, Catherine Flannery Stone.
William is survived by his wife of 39 years, Maggie; son, William Waring Flannery, Jr. and his wife, Beverly Cage Flannery; and Maggie's children, Frances Chamberlain, Georgia Chamberlain and Louise Chamberlain Jimenez. William had five grandchildren, Sylvia Catherine Flannery, Ann Flannery Hunt, William Waring Flannery III, Kathleen Flannery and Robert Waring Flannery. He had seven great-grandchildren.
William was a graduate of Texas A&M University.
He served as President and CEO of Alamo National Bank for many years. William was also a Director of Hemisfair, an active member of the Texas Cavaliers, The Order of the Alamo, The San Antonio Country Club, The Argyle Club and the Conopus Club.
He loved managing the Waring Ranch, playing golf, hunting, fishing, and playing cards.