By-elections to the 45th Canadian Parliament

By-elections to the 45th Canadian Parliament are held to fill vacancies in the House of Commons of Canada between the 2025 federal election and the 46th federal election. The 45th Canadian Parliament has existed since 2025 with the membership of its House of Commons having been determined by the results of the Canadian federal election held on April 28, 2025. The Liberal Party of Canada had a minority government during this Parliament until the three by-elections held on April 13, 2026, where they gained majority status. The Conservative Party of Canada forms the Official Opposition.

A writ for a by-election must be dropped no sooner than 11 days and no later than 180 days after the chief electoral officer is officially notified of a vacancy via a warrant issued by the Speaker. Under the Canada Elections Act, the minimum length of a campaign is 36 days between dropping the writ and election day, but must not exceed 50 days and the by-election must occur on a Monday within that time-frame.

Four by-elections have been held during the 45th Parliament. They took place in the electoral districts of:

• Battle River—Crowfoot, (Alberta), following Conservative MP Damien Kurek's announcement of his pending resignation of his seat on May 2, 2025 to give Pierre Poilievre, the leader of the Conservative Party, an opportunity to re-enter parliament after Poilievre lost his seat in the federal election. Kurek officially resigned on June 17, 2025 and the by-election has been called for August 18, 2025.
• Toronto University—Rosedale, (Ontario), to former Liberal cabinet minister Chrystia Freeland's resignation from Parliament, effective January 9, 2026, following her appointment as economic advisor to the President of Ukraine.
• Scarborough Southwest, (Ontario), due to the resignation of Liberal MP Bill Blair on February 2, 2026, to accept an appointment as Canadian High Commissioner to the United Kingdom.
• Terrebonne, (Quebec), after the Supreme Court of Canada, on February 13, 2026, annulled the one-vote victory by Liberal MP Tatiana Auguste due to a misprint by Elections Canada in return envelopes it produced for mail-in ballots. A minimum of 40 ballots were thought to have been distributed with an incorrect postal code on the return envelope.

A by-election is possible in the Toronto electoral district of Beaches—East York following Liberal MP Nate Erskine-Smith's announcement that he intends to contest the provincial Liberal nomination in Scarborough Southwest and seek a seat in the Ontario legislature. A by-election is also possible in Rosemont—La Petite-Patrie as NDP MP Alexandre Boulerice is seeking the Québec solidaire nomination in Gouin for the next Quebec provincial election, expected in October 2026.

A by-election was called in the federal riding of Battle River—Crowfoot, and was held on August 18, 2025, following the resignation of Conservative MP Damien Kurek. Kurek, who secured re-election with over 80% of the vote in the 2025 federal election on April 28, resigned his seat on June 17. This was done to allow Conservative leader Pierre Poilievre an opportunity to return to Parliament through a by-election after he was unseated in the 2025 Canadian federal election.

The writ for the by-election was drawn up on June 30, 2025 with the date of the vote set for August 18 in order to avoid a conflict with Alberta Heritage Day earlier in the month.

Nominations closed on March 23, at 2 pm local time.

A by-election was held in the federal riding of University—Rosedale in Ontario, Canada, following the January 9, 2026, resignation of incumbent Liberal MP Chrystia Freeland due to her accepting a position as economic advisor to the Office of the President of Ukraine.

The Chief Electoral Officer of Canada received formal notification of the vacancy from the Speaker of the House of Commons of Canada on January 9, 2026. The date of the by-election must be announced between January 20 and July 8, 2026. The by-election must be held on a Monday, at least 36 days but no more than 50 days after the day the by-election is announced. Accordingly, the earliest date that University—Rosedale by-election could have been held was March 2, 2026.

The Liberals announced Danielle Martin as their candidate on January 31.

Serena Purdy, the NDP candidate in this riding in the 2025 federal election, announced on March 3 that she would be the party's candidate.

The Greens announced candidate Andrew Massey on February 12.

Independent Adam Golding announced his candidacy in mid-February; he previously finished last in the riding in the 2025 federal election.

The Centrist Party announced Imran Khan as their candidate on February 16; Khan previously ran in Scarborough Southwest in the 2025 federal election.

The Conservatives announced Don Hodgson as their candidate on March 11.

Martin was elected, holding this seat for the Liberals.

A by-election was held in the federal riding of Scarborough Southwest in Ontario, Canada, following the announced resignation of incumbent Liberal MP Bill Blair on February 2, 2026.

The Chief Electoral Officer of Canada received formal notification of the vacancy from the Speaker of the House of Commons of Canada on February 2, 2026. The date of the by-election must be announced between February 13 and August 1, 2026. The by-election must be held on a Monday, at least 36 days but no more than 50 days after the day the by-election is announced. Accordingly, the earliest date that the Scarborough Southwest by-election could be held is March 23, 2026.

The Liberals announced then–Ontario NDP deputy leader and MPP Doly Begum as their candidate on February 3.

The New Democratic Party is running Fatima Shaban, who was also the party's candidate in 2025.

The Greens announced Pooja Malhotra as their candidate on February 12.

The Centrist Party announced Lyall Sanders as their candidate on February 21.

Begum was elected, holding this seat for the Liberals.

A by-election was held in the federal riding of Terrebonne in Quebec, Canada, after the Supreme Court of Canada, on February 13, 2026, reversed a lower court ruling denying an appeal by a Bloc Québécois candidate, who lost the federal election in Terrebonne riding by a single vote, vacating the seat won by Liberal MP Tatiana Auguste and triggering a byelection. The annulment was due to a printing error by Elections Canada on a return envelope for mail-in ballots which resulted in an envelope containing a vote for the Bloc Québécois candidate being returned to sender after the election.

Auguste was elected by an increased margin according to preliminary results, holding this seat for the Liberals.