Vassar made his debut on the country music scene in the late 1990s, co-writing singles for several country artists, including Tim McGraw, Joe Dee Messina, Collin Raye and Alan Jackson. In 1999, he was named by American Society of Composers, Authors and Publishers, ASCAP as Country Songwriter of the Year.
His debut album, Phil Vassar, was released in early 2000; it produced five hit singles on the U.S. Billboard country singles charts and was certified gold in the United States. He followed it in 2002 with American Chile, Shaken Not Stirred in 2004, and finally Greatest Hits, Vol. 1 in 2006. Prayer of a Common Man, was released in early 2008. He has charted nineteen singles on the Billboard Hot Country Songs charts, including two Number Ones: 2000's Just Another Day in Paradise and 2004s In a Real Love, Traveling Circus in 2009 and Noel in 2011