Finland has become the 20th country to legislate for same sex marriage.
The Finnish parliament passed the ground breaking legislation with 105 politicians supporting it and 95 opposed.
Finland was the last Scandinavian country to approve same sex marriage.
Finnish couples have been able to enter into registered relationships since 2002.
The decision has been welcomed by the US based Human Rights Campaign.
“We commend the elected representatives of Finland for passing such historic legislation ensuring the nation’s LGBT citizens receive the rights they deserve, and we congratulate the LGBT activists and advocates who made this momentous day possible,” said Ty Cobb, Director of HRC Global.
Prior to the vote being taken the country’s Prime Minister Alexander Stubb published an open letter saying that Finland needed to be a country free of discrimination.
“Finland should strive to become a society where discrimination does not exist, human rights are respected and two adults can marry regardless of their sexual orientation,” Prime Minister Stubb wrote.
Rodney Croome, National Director of Marriage Equality Australia said the Finnish decision highlighted how Australia was falling behind other Western democracies.
“Finland joining the rapidly growing list of countries with marriage equality highlights how far Australia is falling behind.”
“But the fact that Finland achieved marriage equality under a centre right government, just like the UK and New Zealand, gives us hope marriage equality can also be achieved under the current Australian government.” Coome said.