According to a note in the IAJGS Public Records Access Alert:
In 2013, Ancestry digitized the Canadian 1921 census and until last month it was available only through Ancestry. Per their agreement with Library and Archives Canada, the 1921 census is now available free at the Library and Archives Canada. Canada has a 92-year privacy act therefore, the first time it would have been available to the public is 2013. In 1921 there were 233 census districts and enumerators collected information on 8,788,433 individuals. The Dominion Bureau of Statistics was authorized to microfilm and destroy the original paper records. The only microfilm copy s an archival holding. The digitized copies were made from microfilm-which is acknowledged on inconsistent quality and some images are not readable. Some of the records did not survive. Access on Library and Archives Canada is free.
To access the census go to: