The vote showed 61.6% of people favoured allowing same-sex couples to Wednesday, the Australian Bureau of Statistics said.
Despite some early criticisms that the use of the postal system would make the survey inaccessible, an overwhelming 79.5 per cent of Australian voters did participate, in what the Chief Statistician called an "outstanding" turnout.
Prior to the official count release, Prime Minister Malcolm Turnbull said it's the "goal" that same sex marriage will be legal in Australia by Christmas.
Various opinion polls point to a majority "yes" vote, possibly as high as 60 per cent.
The bill will be introduced in to the Senate on Wednesday for debate on Thursday and the Labor leader, Bill Shorten, has offered the opposition's support to help "stare down the conservatives seeking to delay marriage equality". At 10am on the dot, we'll know whether Australia voted Yes on same-sex marriage.
"A Yes result would be a massive win for people power - millions of us sent back a Yes vote not just for marriage equality but also for fairness and love", she said.
It will be supported by Labor and the Greens even though the minor party plans to present amendments. Coalition parliamentarians, who were previously required to vote against marriage equality will now be given a free vote, Labor MPs are nearly universally in favour and a majority of crossbenchers will also support the bill.
"It think it indicates what modern Australia is", he told Sky News.
If it is a yes from the public, then PM Malcolm Turnbull has said a private member's bill will be debated in Parliament, with the PM pushing for a vote before Christmas.
Ireland voted for marriage equality in a referendum in 2015.
Cabinet minister Matt Canavan argues the survey result, whichever way it goes, should not be seen as affirmation or rejection of the Smith bill.
Wong said parliament should not be distracted by the Paterson Bill. Ironically to ensure these protections, the bill would override existing state and territory anti-discrimination and freedom-of-speech laws.
A handful of MPs have vowed to ignore the public's will and vote against the bill anyway, but they are few and far between. It already has the support of numerous "no" campaign's biggest advocates.