Hawkes was born in Windsor, Berkshire, to Carol (née Dilworth) and Leonard Hawkes, brother to Tony Hawkes. Chesney was named after the singer and comedian, Chesney Allen. His father is the singer Len 'Chip' Hawkes, formerly with the 1960s band The Tremeloes. His mother is former actress/game show hostess, Carol Dilworth (who appeared in an episode of the 1960s version of Randall and Hopkirk (Deceased) called "For The Girl Who Has Everything"). Keely Hawkes, his sister, was the lead singer of '90s band Transister, and is currently a songwriter based in Los Angeles. He attended Charters School in Sunningdale.

Hawkes' career began at 19, when he appeared as the title character in the film Buddy's Song. In March 1991, he released his biggest single "The One and Only" from the film's soundtrack, on which his younger brother, Jody, was the drummer. Written By Nik Kershaw, the song was later featured in the opening credits of Doc Hollywood (1991), starring Michael J. Fox; in the 2009 movie Moon, as the song Sam Rockwell wakes up to every morning; and again in the 2011 film Source Code (also directed by Moon director Duncan Jones) as the cell phone ringtone of Michelle Monaghan's character. The single spent five weeks at number one. He has released eight singles including "I'm a Man Not a Boy" and "Another Fine Mess".