Delegates at the party's conference in Brighton cheered after it was agreed that independent schools should be integrated into the state sector.
This would include the withdrawal of charitable status and "all other public subsidies and tax privileges", including business rate exemption.
Shadow schooling secretary Angela Rayner stated she is going to process the Social Mobility Fee - which the social gathering would rename the Social Justice Fee - with "integrating private schools".
Ryan Quick, the member who proposed the motion, noted that the "old boys' network" was preventing the country from moving forward.
The take-over of private schools would not be without cost, however, with the BBC noting that it would result in some 600,000 formerly-independent school pupils - the school population of Wales - to be educated by the public purse, an estimated £3.5 billion on top of the education budget.
John Wiseman, a member of the Unite union and former teacher, asks "How can it be right in 21st century Britain to still have a feudal education system where a privileged few receive tax-subsidised education on the back of ordinary working people?"
The motion adds universities would have to admit the same proportion of private school students as in the wider population, now 7 percent.
"Endowments, investments and properties" would also be redistributed across the country's schools.
"Every child deserves a world class education, not only those who are able pay for it, and I'll be proud to campaign on this manifesto pledge at the next election".
Head of Dover College Gareth Doodes, who attended Eastbourne College, said on Twitter: "I went to @EBCollegeLife because my parents made a choice and then made enormous sacrifices". Tearing down excellent schools does not improve our education system.
"If implemented, it will be an act of unprecedented vandalism".
He added it would "threaten" the jobs of teachers and support staff, noting: "Empty promises of transferring over to a comprehensive state system ignore employment law and basic humanity".