Statistical survey for gay marriage poll

STEPS TO MARRIAGE EQUALITY

* Senate to vote this week on legislation to run a compulsory plebiscite on November 25.

* If that doesn't pass, the government will ask the Australian Bureau of Statistics to collect "statistical information" from every registered voter on their views whether same-sex couples should be allowed to marry.

* Ballot papers to be sent out from September 12 and the result finalised by November 15.

* Participation in the ABS survey (previously known as "postal plebsicite") will be voluntary.

* If the nation votes yes (in either form of plebiscite) the government will allow parliament to debate and vote on a private member's bill to legalise same-sex marriage, ideally before parliament rises on December 7.

* If the nation votes no, the government will not help any MP bring a private bill to a vote.

* The ABS option will cost $122 million.

* Government believes it's on firm legal ground, citing the ABS running a nation-wide poll on a new national anthem in 1974.