Ontario Conservative MP Scott Aitchison has announced he will resign his seat of Parry Sound-Muskoka at the end of the current fall parliamentary sitting.

In a letter released to constituents today, Aitchison said after 30 years of public life, he plans to explore other opportunities.

Aitchison ran for the party leadership in 2022 and has served as the opposition’s housing critic. He was a municipal councillor and then mayor of Huntsville, Ont., for 25 years before running for the Conservatives federally in 2019.

Aitchison’s impending resignation was first reported by The Hill Times Tuesday.

He is set to become the 12th MP to resign since January and the eighth Conservative to leave the caucus in the last 11 months.

Four Conservatives crossed the floor to join the Liberals, with Nova Scotia MP Chris D’Entremont the first to exit last November. Quebec MP Richard Martel left this summer for a Senate appointment. Saskatchewan’s Cathay Wagantall and Ontario’s Larry Brock both resigned within the last month.

Aitchison said it has been the “honour of his lifetime” to serve the people of his community for the last three decades.

“To the people of Parry Sound—Muskoka who placed their trust in me, and those who I disagreed with but promised passionate representation to, I hope I have made you proud,” Aitchison said in his resignation letter.

“I want to thank my incredible staff who have served me and the people of Parry Sound—Muskoka with distinction. None of this would have been possible without you.”

He closed his statement by thanking his Conservative colleagues and calling on them to continue to “champion efforts to make life more affordable for all Canadians.”

Conservative Leader Pierre Poilievre issued a statement thanking Aitchison for his public service and wishing him all the best in his next chapter.

“Scott’s greatest strength has always been his connection to his home. Whether fighting for local workers and businesses, helping people navigate the federal government, or championing a community fund to support housing, food security and mental health in Parry Sound—Muskoka, he never forgot who sent him to Ottawa,” Poilievre said.

There are currently six vacancies in the House of Commons requiring byelections.

Elections Canada estimates a byelection costs about $2 million, but that figure can vary depending on the riding.

This report by The Canadian Press was first published Sept. 30, 2026.