On Friday, August 3, 2018, the Chief Electoral Officer of Canada, Stéphane Perrault, received official notice from the Speaker of the House of Commons that the seat for Outremont (Quebec) is vacant. A by-election will take place to fill the vacant seat.
The date of the by-election must be announced between August 14, 2018, and January 30, 2019. This announcement signals the start of the by-election period.