By-elections to the 20th Canadian Parliament

By-elections to the 20th Canadian Parliament were held to fill vacancies in the House of Commons of Canada between the 1945 federal election and the 1949 federal election. The Liberal Party of Canada led a working majority government for the 20th Canadian Parliament, though was technically a minority government during World War II.

Shortly before the dissolution of the 20th Canadian Parliament, Newfoundland joined Confederation as the tenth province. Unlike the case when the provinces such as Manitoba, British Columbia and Prince Edward Island joined, by-elections were not called to fill the new province's seven seats.

Eighteen vacant seats were filled through by-elections.