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. By-election Date Incumbent Party Winner Party Cause RetainedNicolet—YamaskaFebruary 7, 1949Lucien Dubois Independent LiberalRenaud Chapdelaine Progressive ConservativeDeathNoCarletonDecember 20, 1948George Russell Boucher Progressive ConservativeGeorge A. Drew Progressive ConservativeResignation to provide a seat for DrewYesLaval—Two MountainsDecember 20, 1948Liguori Lacombe IndependentLéopold Demers LiberalResignationNoMarquetteDecember 20, 1948James Allison Glen LiberalStuart Sinclair Garson LiberalResignationYesDigby—Annapolis—KingsDecember 13, 1948James Lorimer Ilsley LiberalGeorge Clyde Nowlan Progressive ConservativeResignationNoAlgoma EastOctober 25, 1948Thomas Farquhar LiberalLester B. Pearson LiberalCalled to the SenateYesRosthernOctober 25, 1948Walter Adam Tucker LiberalWilliam Albert Boucher LiberalResignationYesOntarioJune 8, 1948W. E. N. Sinclair LiberalArthur Henry Williams CCFDeathNoVancouver CentreJune 8, 1948Ian Alistair Mackenzie LiberalRodney Young CCFCalled to the SenateNoYaleMay 31, 1948Grote Stirling Progressive ConservativeOwen Lewis Jones CCFResignationNoYork—SunburyOctober 20, 1947H. Francis G. Bridges LiberalMilton Gregg LiberalDeathYesHalifaxJuly 14, 1947William Chisholm Macdonald LiberalJohn Dickey LiberalDeathYesCartierMarch 31, 1947Fred Rose Labor-ProgressiveMaurice Hartt LiberalSeat declared vacant by resolution of the House of CommonsNoRichelieu—VerchèresDecember 23, 1946Arthur Cardin IndependentGérard Cournoyer LiberalDeathNoParkdaleOctober 21, 1946Herbert A. Bruce Progressive ConservativeHarold Timmins Progressive ConservativeResignationYesPortage la PrairieOctober 21, 1946Harry Leader LiberalCalvert Charlton Miller Progressive ConservativeDeathNoPontiacSeptember 16, 1946Wallace McDonald LiberalRéal Caouette Social CreditDeathNoGlengarryAugust 6, 1945William B. MacDiarmid LiberalWilliam Lyon Mackenzie King LiberalResignation to provide a seat for Mackenzie KingYes
See also List of federal by-elections in Canada
Sources Parliament of Canada–Elected in By-Elections