[2][5] After starting boxing at the age of 12 at the local Police and Community Youth Club (PCYC), he soon began appearing in amateur competitions, winning 98 out of 113 bouts.
[6] After missing out on the Olympics Dib traveled to Sheffield to train with Prince Naseem Hamed, who encouraged him to turn professional.
[2] On 30 July 2008, Billy Dib faced South African Zolani Marali for the IBO super featherweight title.
Although Marali had a greater reach, and despite being knocked down in the third round, Dib was able to win on a unanimous points decision (116–114, 116–112 and 114–113), allowing him to capture the title.
[11] Subsequently, the NSW Boxing Authority announced that they are undertaking an investigation into the events,[12] and at their monthly board meeting on 4 August, the officials determined to change the result to a no-contest.
[13] After nine straight victories, in July 2011 Dib took on longtime contender Jorge Lacierva and captured the IBF Featherweight belt via Unanimous Decision.
Occasionally getting involved in some wild exciting exchanges, for the most part he boxed a disciplined fight, out-boxing his smaller opponent.
On 19 November 2011, Billy made the first defense of his title, knocking out Italian challenger Alberto Servidei in 2:38 of the first round from a left hook to the body.
[16] After a brief retirement following a loss to Tevin Farmer in 2018, Dib returned to the ring in August 2019, losing in a WBC welterweight title fight to Amir Khan.