MP for Parry Sound-Muskoka Scott Aitchison rises during Question Period on Parliament Hill in Ottawa, on June 18. He has represented the riding since 2019.Adrian Wyld/The Canadian Press
High-profile Conservative MP Scott Aitchison will resign his seat by the end of the year, creating yet another vacancy on Pierre Poilievre’s benches, sources say.
Mr. Aitchison, the MP for Parry Sound-Muskoka and the party’s housing critic, informed Mr. Poilievre last week of his decision to resign, two sources with knowledge of the discussion told The Globe and Mail.
The Globe is not naming the sources as they were not authorized to publicly discuss Mr. Aitchison’s decision. Mr. Aitchison did not immediately return a call seeking comment.
The two sources both characterized Mr. Aitchison’s decision to leave as a desire to try something else beyond elected life; he has been in politics since 1994.
Mr. Aitchison’s departure at the end of the current parliamentary session follows Conservative MP Larry Brock’s announcement this summer that he was stepping down from his seat in Ontario’s Brantford-Brant South riding. Mr. Brock officially resigned his seat earlier this month.
Ontario Conservative MP Larry Brock formally resigns from House of Commons
Saskatchewan MP Cathay Wagantall resigned her seat on Aug. 31. She had announced in June that she was leaving, and had previously said she would not seek re-election.
By-elections have not been called yet to fill either vacancy.
In addition to Mr. Brock and Ms. Wagantall’s departures, four Conservative MPs have crossed the floor to the Liberals since last November. Another, Quebec MP Richard Martel resigned his seat for a senate appointment.
The Conservatives subsequently lost his riding in the August by-election.
Mr. Aitchison has represented Parry Sound-Muskoka since 2019 and won his seat in the 2025 election with 52.2 per cent of the vote.
He ran against Mr. Poilievre for the leadership of the Conservatives in 2022, positioning himself as a moderate voice for the party; he finished fifth.
News of his impending departure was first reported by CTV.
The most recent polling data from Nanos Research suggests support for the Liberals stands at 49.9 per cent, with the Conservatives at 27.9 percent.
Mr. Carney has a majority government with 173 seats. The Conservatives currently hold 137, including Mr. Aitchison. There are six vacancies.