As a boy growing up in Memphis, Tennessee, Sanderson delivered The Commercial Appeal newspaper, played youth baseball, and attended Bellevue Baptist Church.
William Sanderson: (on his previous drinking problem) You know, there are actors who sit around and make themselves into outlaws. I would get the roles mixed up with myself. But nobody's been given more second chances than I have.
William Sanderson: (on hanging out with Elvis Presley while growing up in Memphis) I did some pretty dumb things to impress Elvis, like playing too rough in football or hitting his car too hard in the bumper cars at the park, but he never really got mad.