Prior to entering television, Deval worked as a journalist for the sports website Canapsports (2012–2013) and served as general manager of Bercy Football Club from 2013 to 2016.[9] In 2015, he completed a stint at Mensquare, where he produced a large number of articles, interviews, and reports.[9][8]
Deval joined the newsroom of iTélé (later renamed CNews) in 2016 as a trainee. He progressively held various positions within the channel, including reporter, editor, and chief editor for Pascal Praud's programmes.[2][9] He has described his trajectory as that of a "couteau suisse" (Swiss army knife), emphasising that the versatility of working behind the scenes helped him develop as a presenter.[10]
On 17 July 2023, he took over the presentation of L'Heure des pros during Pascal Praud's summer holidays, marking a decisive step in his career.[8] On 24 February 2024, he achieved a personal audience record of approximately 800,000 viewers for a weekend edition of the programme.[2][11] He has since become the regular weekend presenter of L'Heure des pros on CNews, while Praud presents the show from Monday morning to Thursday morning.
Beyond L'Heure des pros, Deval presents several other programmes on CNews: Face à Face, in which he hosts two editorialists with opposing views;[4] Face à Philippe de Villiers, a weekly show in which Philippe de Villiers reviews the week's news alongside a guest;[5] and Soir Info on Friday evenings.[12]
On 25 November 2025, Deval served as host of Face à vous, a live debate event held at the Dôme de Paris (Palais des Sports) bringing together journalists and editorialists from CNews, Europe 1, and the Journal du dimanche before an audience of 4,000 people.[13]
In parallel with his television work, Deval hosts On marche sur la tête on Europe 1, a weekday afternoon programme broadcast from Monday to Friday between 4 p.m. and 6 p.m. in co-broadcast with CNews, covering current affairs and politics with listener participation.[7] He also presents Eliot Deval et vous, a two-hour weekend programme on the same station.[6]
In January 2024, L'Heure des pros began to be co-broadcast on Europe 1 from 9 a.m. to 9:30 a.m. on weekday mornings, further increasing the synergy between the two outlets within the Bolloré media group.
In an interview on Le Buzz TV in April 2024, Deval rejected the widespread perception that he was Pascal Praud's protégé, describing it as "an urban legend". He also defended CNews's editorial line, stating that the channel was "not an opinions channel without an 's', but a news channel with opinions".[2]