House of Commons of Canada

The House of Commons of Canada (French: Chambre des communes du Canada) is the lower house of the Parliament of Canada. Together with the Crown and the Senate of Canada, they comprise the bicameral legislature of Canada.

The House of Commons is a democratically elected body whose members are known as members of Parliament (MPs). The number of MPs is adjusted periodically in alignment with each decennial census. Since the 2025 federal election, the number of seats in the House of Commons has been 343.

Members are elected by simple plurality ("first-past-the-post" system) in each of the country's electoral districts, which are colloquially known as ridings. MPs may hold office until Parliament is dissolved and serve for constitutionally limited terms of up to five years after an election. Historically, however, terms have ended before their expiry and the sitting government has typically dissolved parliament within four years of an election according to a long-standing convention. In any case, an act of Parliament now limits each term to four years. Seats in the House of Commons are distributed roughly in proportion to the population of each province and territory. However, some ridings are more populous than others, and the Canadian constitution contains provisions regarding provincial representation. As a result, there is some interprovincial and regional malapportionment relative to the population.

The British North America Act 1867 (now called the Constitution Act, 1867) created the House of Commons, modelling it on the British House of Commons. The lower of the two houses making up the parliament, the House of Commons, in practice holds far more power than the upper house, the Senate. Although the approval of both chambers is necessary for legislation to become law, the Senate only occasionally amends bills passed by the House of Commons and rarely rejects them. Moreover, the Cabinet is responsible primarily to the House of Commons. The government stays in office only so long as they retain the support, or "confidence", of the lower house.

The traditional meeting chamber of the House of Commons is in the Centre Block of the Parliament Hill complex in Ottawa. However, as of 2025^[update], Centre Block is undergoing renovations; the House of Commons is therefore meeting in a temporary chamber in the West Block of the complex.

The term derives from the Anglo-Norman word communes, referring to the geographic and collective "communities" of their parliamentary representatives and not the third estate, the commonality. This distinction is made clear in the official French name of the body, Chambre des communes. Canada and the United Kingdom remain the only countries to use the name "House of Commons" for a lower house of parliament. The body's formal name is: The Honourable the Commons of Canada in Parliament assembled (French: l’Honorable Chambre des communes du Canada, en Parlement assemblée).

The House of Commons came into existence in 1867, when the British Parliament passed the British North America Act 1867, uniting the Province of Canada (which was divided into Quebec and Ontario), Nova Scotia and New Brunswick into a single federation called Canada. The new Parliament of Canada consisted of the monarch (represented by the governor general, who also represented the Colonial Office), the Senate and the House of Commons. The Parliament of Canada was based on the Westminster model (that is, the model of the Parliament of the United Kingdom). Unlike the UK Parliament, the powers of the Parliament of Canada were limited in that other powers were assigned exclusively to the provincial legislatures. The Parliament of Canada also remained subordinate to the British Parliament, the supreme legislative authority for the entire British Empire. Greater autonomy was granted by the Statute of Westminster 1931, after which new acts of the British Parliament did not apply to Canada, with some exceptions. These exceptions were removed by the Canada Act 1982.

From 1867, the Commons met in the chamber previously used by the Legislative Assembly of Canada until the building was destroyed by fire in 1916. It relocated to the amphitheatre of the Victoria Memorial Museum – what is today the Canadian Museum of Nature, where it met until 1922. Until the end of 2018, the Commons sat in the Centre Block chamber. Starting with the final sitting before the 2019 federal election, the Commons sits in a temporary chamber in the West Block until at least 2028, while renovations are undertaken in the Centre Block of Parliament.