In response to the 2001 Census of Population and Housing question, Australians’ stated religious affiliations were: 27% Catholic, 21% Anglican, 21% other Christian denominations and 5% non-Christian religions. Just over one-quarter of all Australians either stated they had no religion, or did not adequately respond to the question to enable classification of their religion.

A question on religious affiliation has been asked in every census taken in Australia, with the voluntary nature of this question having been specifically stated since 1933. In 1971, the instruction ‘if no religion, write none’ was introduced. This saw a seven-fold increase from the previous census year in the percentage of Australians stating they had no religion. Since 1971, this percentage has progressively increased to about 16% in 1996 and 2001.