Same-sex couples will be able to marry from early January once the governor- general signs off on new marriage equality laws.
Sir Peter Cosgrove will give the laws royal assent on this morning when he is visited by Prime Minister Malcolm Turnbull in Canberra.
Before that an elated Mr Turnbull has been encouraging his fellow Australians to start making wedding preparations.
"It is a big Australian hug for all same-sex couples, saying we love and respect you, now go out there and get married," he told the Seven Network.
Mr Turnbull described the postal survey as a game-changer for the issue, now resolved after years of debate.
He criticised Labor for not progressing the matter when in office but said the victory now belongs to the whole parliament.
The passage of the laws would not put religious freedoms at risk or traditional marriage, he insisted.
"People that think gay people making a commitment is is a threat to her marriage fails to realise that the real threat is lack of commitment," Mr Turnbull said.
The new laws cleared parliament unchanged yesterday evening after a marathon debate lasting 56 hours and despite a push from conservative MPs for additional religious protections.
Only four MPs in the House of Representatives voted against the private bill, a week after the legislation was agreed to by the Senate.
Mps broke into song after same-sex marriage was legalised, singning, "We are one, but we are many and from all the lands on earth we come. We’ll share a dream and sing with one voice. I am, you are, we are Australian."
Labor leader Bill Shorten said the new law spoke for a modern, "inclusive and fair" Australia.
Same-sex couples will be able to lodge formal intentions to wed from tomorrow allowing them to marry from January 9.
Gay couples who tied the knot overseas will have their unions officially recognised as soon as the laws gain royal assent.