Williams, a 6-foot-6, 273-pound offensive tackle from West Roxbury (Mass.) Catholic Memorial, selected the Tar Heels over co-finalist Boston College. He's ranked a four-star prospect by Scout.com.
In addition to his two co-finalist, Williams took official visits to Virginia and Wake Forest.
Williams told Inside Carolina Wednesday that his decision was made a couple of weeks back. However, he wanted to publicly announce his decision at the U.S. Army All-American Bowl, which was televised live by NBC.