Provincial politics d'Entremont was first elected MLA for
Argyle in the
2003 election, and re-elected in the
2006,
2009,
2013 and
2017 elections. In August 2003, d'Entremont was appointed to the
Executive Council of Nova Scotia as Minister of Agriculture and Fisheries, and Minister of Acadian Affairs. He later served as Minister of Health, Minister of Community Services, Minister responsible for the Youth Secretariat, and Chair of the Senior Citizens' Secretariat. He briefly served as the interim Minister of Finance following the death of
Michael Baker in March 2009. Those duties were shifted to
Jamie Muir seven days later. In November 2018, d'Entremont announced he was seeking the
Conservative nomination in
West Nova for the
2019 federal election. He won the nomination in June 2019. d'Entremont resigned his provincial seat in July 2019.
Federal politics On
21 October 2019, d'Entremont was elected as the Member of Parliament in West Nova, defeating
Liberal candidate Jason Deveau (the incumbent MP, Liberal
Colin Fraser, did not seek re-election). He was the only non-Liberal MP elected from Nova Scotia and representing the easternmost riding among Conservatives elected in the 2019 federal election. In 2019, Conservative leader
Andrew Scheer appointed d'Entremont to be Shadow Minister of Official Languages and a member of the Standing Committee on Official Languages. He served as Shadow Minister for Intergovernmental Affairs in
Erin O'Toole's Shadow Cabinet. D'Entremont also sat as a member of the Standing Committee on Health. On
20 September 2021, d'Entremont was re-elected as the MP for West Nova, defeating Liberal challenger Alxys Chamberlain by almost 20 percentage points. He was appointed as deputy speaker in November. On
28 April 2025, he won re-election in the newly renamed
Acadie—Annapolis riding against former provincial Liberal MLA
Ronnie LeBlanc. He was the sole member of his party to win a federal riding in Nova Scotia in the 2025 election. On 4 November 2025, he left the
Conservative Party and crossed the floor to join the
Liberals in support of Prime Minister
Mark Carney's government, citing issues with the leadership of Conservative Party leader
Pierre Poilievre. This decision sparked passionate responses from constituents and other members of Parliament. d'Entremont's party crossing came shortly after the
tabling of
budget 2025, and with his crossing, the Liberal
minority government became two seats away from forming a
majority government. Shortly after the floor crossing the
Royal Canadian Mounted Police launched an investigation into online threats made against d'Entremont. ==Electoral record==