Same-sex marriage in Australia became legal as the Marriage Amendment (Definition and Religious Freedoms) Act 2017 came into effect. Same-sex marriage in Australia: Same-sex marriage has been legal in Australia since 9 December 2017. Legislation permitting same-sex marriage, the Marriage Amendment Act 2017, became law on 8 December 2017 and came into effect the next day. This immediately recognised overseas same-sex marriages. The first same-sex wedding under Australian law was held on 15 December 2017. The passage of the law followed a voluntary postal survey of all Australians, in which 61.6% of respondents supported the legalisation of same-sex marriage. Australia was the second country in Oceania, after New Zealand, and the 23rd in the world to allow same-sex couples to marry nationwide. Prior to legalisation, 22 bills to allow same-sex marriage were introduced to Parliament between September 2004 and May 2017. These failed attempts came after the Howard government amended the Marriage Act 1961 in 2004 to codify the then-exclusively heterosexual common law definition of marriage. The Australian Capital Territory passed a same-sex marriage law in December 2013 that was struck down by the High Court for inconsistency with federal law. December 9, 2017. Wiki link