In 1880 a Baptist Union of Canada was formed. Since the churches were located chiefly in the central provinces, the name was changed in 1888 to its present Baptist Convention of Ontario and Quebec. In 1944, the BCOQ joined with the United Baptist Convention of the Maritimes and the Baptist Union of Western Canada to form the Canadian Baptist Federation.
The Convention Assembly meets annually, electing officers, addressing issues, and offering workshops. According to its mission statement, "[t]he Convention exists to assist our churches to carry out their individual mission for Christ and to do that which we believe God calls us to do together." The Canadian Baptist is a quarterly newsletter published by the Convention. McMaster Divinity College is affiliated with McMaster University in Hamilton, Ontario. Convention offices are located in Etobicoke, Ontario. BCOQ is a member of the Evangelical Fellowship of Canada and Canadian Baptist Ministries.
Around the turn of the 20th century, the Convention was composed of over 450 churches with about 44,000 members. Due to internal controversies, such as fundamentalism vs. modernism, and the strength of the United Church of Canada in Ontario and the Roman Catholic Church in Quebec, the BCOQ has declined to about 380 churches in 2003, with an estimated 45,000 members.