In 1999, McCartney joined the American pop boy band Dream Street, and was a member until 2002. Jesse McCartney has described the experience as a good "stepping stone" for his solo career. The group earned a gold record with their debut CD, and broke up while touring with Aaron Carter. At fifteen, he began work on a solo career with a local band, featuring musicians Dillon Kondor (guitar), Peter Chema (bass), Katie Spencer (keyboards), Alex Russeku (drums), Karina LaGravinese (background vocals), Sharisse Francisco (background vocals), and under the management of Ginger McCartney and Sherry Goffin Kondor, who co-produced his first album, Beautiful Soul.

McCartney released his first solo EP in July 2003. The album featured three songs: "Beautiful Soul", "Don't You" and "Why Don't You Kiss Her". In 2004, he performed a duet with Anne Hathaway, "Don't Go Breaking My Heart", which is featured on the Ella Enchanted soundtrack.