Official Opposition (Canada)

The Official Opposition (French: Opposition officielle) is the largest party of the parliamentary opposition, which is composed of members of Parliament (MPs) who are not in government. Typically, it is the second-largest party in the House of Commons.

The Official Opposition is viewed as the caucus tasked with keeping the government in check. It is also generally viewed as the alternative government or "government in waiting". The Official Opposition maintains a shadow cabinet, with the leader of the Official Opposition at its head, of members of Parliament (MPs) and senators who often have the same portfolio areas of interest as actual ministers. The spokesperson for each portfolio is known as an opposition critic. In the event the government loses the confidence of the House or the Official Opposition party wins a general election, the party is ready to become the government.

The current Official Opposition is the caucus of the Conservative Party, assuming the role following its loss of power in the 2015 federal election. The Opposition was led by Pierre Poilievre, who became Conservative leader following the 2022 leadership election, until he lost his bid for re-election in Carleton in the 2025 federal election, a riding he, prior to the election, held since 2004. As a result, Andrew Scheer will take over from Poilievre as leader, while Poilievre will seek to be elected in a yet to be called by-election for the Battle River—Crowfoot riding of Alberta in an attempt to return to the House of Commons.