Schoening grew up in Philadelphia, Pennsylvania, and decided at an early age that he wanted to be a broadcaster. One of his early influences was By Saam, who was broadcasting games for the Philadelphia Phillies when Schoening was growing up. Schoening attended West Catholic High School and one year at Temple University, before transferring to the American Academy of Broadcasting in Philadelphia. After graduating from the six-month program, he got his first job in radio in Illinois.
Schoening worked in Pana, Illinois for about a year, before moving to Lamesa, Texas. In Lamesa, he did radio broadcasts for the Lamesa High School Golden Tornados, including football, basketball, and baseball games. He spent three years in Lamesa before moving again, this time to Huntsville, Texas.
Schoening began in Huntsville at age 23, broadcasting games for Sam Houston State University, including basketball, football, and a little baseball. He stayed in Huntsville for six years, from 1983 to 1989.
In 1989, Schoening was hired to broadcast sports for the University of Texas in Austin. During his first three years in Austin, Schoening served as the color analyst on Texas Longhorns football and basketball, with play-by-play announcers Brad Sham and Jerry Trupiano. After Sham and Trupiano left, Schoening was hired to take over play-by-play for both Longhorn football and basketball, a position he would hold for nine years (through 2001). During this time, Schoening's primary color commentator was Craig Way. Schoening also did play-by-play for Longhorn baseball for all 12 years he was in Austin.
During his time in Austin, Schoening also hosted an afternoon sports radio talk show, first at KLBJ, and then at KVET, after the latter gained the rights to broadcast Longhorn games. He sometimes had co-hosts for these shows, including Jeff Ward and Craig Way. One of these talk shows titled "Sportsday," which Schoening co-hosted with Ward, won a 1996 "Best of Austin" award from the Austin Chronicle for "Best Talk Radio Show."
In September 2001, Schoening was hired as the radio voice of the San Antonio Spurs. Because of the timing of the hire so close to college football season, Schoening called games for both the Spurs and Longhorn football during the fall of 2001.
As of the 2015–16 NBA season, Schoening is in his 15th season with the Spurs. During that time, the Spurs have won four NBA championships (in 2003, 2005, 2007 and 2014). In addition to calling games on the radio, Schoening also writes a blog for the official Spurs website, entitled "20 Second Timeout."
Schoening lives in Austin with his wife, Gerry. They have two sons: Eric, who is a meteorologist with the National Weather Service in Salt Lake City, and Karl, who is a student at Texas State University and broadcast high school football games with Bill during the 2011 NBA lockout.