When the Communist Party of Canada was banned in 1941 it ran candidates as the Labour Progressive Party. The LPP only ever elected one Member of Parliament under its own banner, Fred Rose, who was elected in a 1943 by-election in Montreal and sat in the House of Commons until 1947 when he was charged and convicted with spying for the Soviet Union and expelled from the House of Commons. Dorise Nielson was elected to the House of Commons in 1940 from Saskatchewan as a Progressive Unity MP but was defeated in 1945 when she ran for re-election as an LPP candidate.

In provincial politics, two LPP members, A. A. Macleod and J. B. Salsberg, sat in the Legislative Assembly from 1943 to 1951 and 1955 respectively. The party also elected a number of members to city councils and school boards in various Canadian cities such as Jacob Penner in Winnipeg and other alderman and trustees in Vancouver and Toronto.

The leader of the party was Tim Buck.

See also: List of political parties in Canada