Indonesia's parliament has approved a criminal code that bans sex outside marriage with a punishment of up to one year in jail.
The new laws are a part of a raft of legal changes that critics say undermine civil liberties in the world's third-largest democracy.
The new code will apply to Indonesians and foreigners alike and will also prohibit unmarried couples from living together and sharing a bed.
It was passed with support from all political parties and despite warnings from business groups that it could scare away tourists and harm investment.
However, the code will not come into effect for three years to allow for implementing regulations to be drafted.
Currently, Indonesia bans adultery but not premarital sex.
The laws also include bans on black magic, insulting the president or state institutions, spreading views counter to state ideology and staging protests without notification.
Critics say the new laws can be used to police morality in the world's largest Muslim-majority nation, which has seen a rise in religious conservatism in recent years.
The public response in Indonesia to the new code has been muted so far, with only small protests held in the capital on Monday and Tuesday.
