In 2022 he signed a professional deal with
Boxxer, training with
SugarHill Steward. On 3 February 2024 at
Wembley Arena in London, Whittaker defeated Khalid Graidia via fifth round technical knockout. On 31 March 2024, Whittaker fought at
The O2 Arena in London on the undercard of a British heavyweight title fight between
Fabio Wardley and
Frazer Clarke, defeating Leon Willings via unanimous decision. On 15 June 2024, Whittaker won the
IBF International
light-heavyweight title after defeating 12–0
Ezra Arenyeka by unanimous decision. On 12 October 2024, Whittaker made his first defence of his IBF International light-heavyweight title against
Liam Cameron on the undercard of
Artur Beterbiev vs. Dmitry Bivol. During the bout both boxers became entangled as Whittaker pulled Cameron towards the ropes, resulting in their tumbling over and Whittaker being forced to withdraw due to an injury. The fight subsequently went to the judges' scorecards, as per the rules of the
British Boxing Board of Control, with both boxers receiving a 58–57 score respectively as well as a 58–58 score, resulting in a
split decision technical draw. Whittaker faced Cameron in a rematch in Birmingham on 20 April 2025. He won by stoppage in the second round. In October 2025, he signed a long-term contract with
Eddie Hearn led
Matchroom Boxing.. A month later on 29 November, Whittaker stopped Benjamin Gavazi in the first round of their fight at the
National Exhibition Centre in Birmingham to win the vacant
WBC Silver light-heavyweight title. Whittaker knocked out Braian Suarez in round one at
Liverpool Arena in Liverpool on 18 April 2026. ==Public image==