Marking some of the toughest social media controls in the world, Australia's House of Representatives passed the bill 102 votes to 13 after Prime Minister Anthony Albanese's centre-left Labor government secured bipartisan support for the ban.
The Senate is expected to debate the bill later on Wednesday, with the government keen to ensure it is passed by the end of the parliamentary year on Thursday.
Albanese has argued that excessive use of social media poses risks to the physical and mental health of children and is looking for support from parents.
The planned law would force social media platforms to take reasonable steps to ensure age-verification protections are in place. Companies could be fined up to 32 million USD for systemic breaches.
Australia plans to trial an age-verification system that may include biometrics or government identification to enforce the ban.