The riding was originally created by the
British North America Act 1867 which preserved existing electoral districts in
Lower Canada. It was abolished in 1996 into
Repentigny and
Terrebonne—Blainville. It was recreated during the
2012 federal electoral redistribution from parts of
Terrebonne—Blainville (51%) and
Montcalm (49%), and consisted solely of the city of
Terrebonne. After the
2022 Canadian federal electoral redistribution, the southwestern corner of the city was transferred to
Thérèse-De Blainville.
2025 federal election The riding drew headlines in the
2025 federal election, as it was initially called for the
Bloc Québécois, but its recount led to
Liberal candidate
Tatiana Auguste winning by a margin of one vote, the narrowest result in the country. One voter in the district had her ballot returned as undeliverable due to an incorrect
postal code printed on the pre-addressed ballot return envelope from
Elections Canada; had her vote for the Bloc Québécois candidate been counted, the result would have been tied. After Elections Canada stated that it did not have
legal standing to overturn the judicial recount, the Bloc Québécois announced it would be asking the
Superior Court of Quebec for a new by-election to be held. On October 27, the court ruled that a byelection would not be held. On November 3, Sinclair-Desgagné announced that she would be appealing the ruling to the
Supreme Court of Canada. On February 13, 2026, the
Supreme Court annulled the result of the election in the riding, triggering a
federal by-election. The by-election was held in April 2026, with Auguste winning by a margin of 731 votes, keeping the seat in Liberal control. ==Demographics==