"19 Somethin'" is a song written by David Lee and Chris DuBois, and recorded by American country music singer Mark Wills. It was released in September 2002 as the first single from his Greatest Hits album. The song spent six weeks at number one on the Hot Country Songs chart in early 2003. It also reached number 23 on the Hot 100 chart and was the longer-lasting of Wills's Number One hits.