A couple poses for a photo during the celebration event at the Government house in Bangkok, Thailand, on June 18, 2024.

Thailand has become the first country in Southeast Asia to legalize same-sex marriage after King Maha Vajiralongkorn approved a law passed by the parliament.

The royal approval for the same-sex law was announced in a gazette notification late on Tuesday, with a clause that the legislation takes effect 120 days from the date of publication. The new law will allow same-sex couples to legally register marriages starting January 22.

Under the new law, Thailand will recognize marriage registrations of same-sex partners aged 18 and above, along with their rights to inheritance, tax allowances and child adoption, among others. This is seen as a victory for LGBTQ activists, who have campaigned for over a decade for the same marriage rights as heterosexual couples.

Although Thai laws have protected LGBTQ people from most kinds of discrimination since 2015, attempts to formalize marriage rights had stalled. The previous Prime Minister’s administration advocated for the law, arguing it would also enhance Thailand’s reputation as an LGBTQ-friendly tourist destination.

Thailand becomes the third country in Asia to recognize same-sex marriage, after Taiwan and Nepal, and joins a group of approximately 40 nations around the world that guarantee equal marital rights. This achievement makes Thailand stand out in Southeast Asia where there has been little progress in recognizing the rights of the LGBTQ community, which often faces discrimination.

Thailand’s House of Representatives and the Senate had overwhelmingly voted in favor of the bill earlier this year. On Tuesday, Prime Minister expressed her delight over the royal approval for the law.

“Thank you for the support from all sectors. It is a joint fight for everyone,” she posted on X.

The so-called marriage equality bill is technically an amendment to Thailand’s Civil and Commercial Code. The government is expected to follow through with a legislation to recognize gender identity.