Top private schools attended by members of the Cabinet avoided charging £65 million in VAT on their fees last year due to their charitable status.
Analysis by Labour of accounts submitted to the Charity Commission found gross fee income received by elite schools where top Tories were pupils amounted to more £329m in 2021.
This left more than £65m in uncollected VAT, which most private schools are exempt from paying on fees due to their charitable status.
Rishi Sunak's former school, Winchester College, and Charterhouse, where Chancellor Jeremy Hunt was a pupil, both avoided charging nearly £6m in VAT savings.
Millfield, attended by the Defence Secretary, Ben Wallace, avoided charging more than £8m in fees, the most of any of the Cabinet Ministers’ former schools.
Keir Starmer told the PM to "end the Tory scandal" of massive tax breaks for private schools in a fierce PMQs clash, where he declared: "Trickle down education is nonsense".
He told MPs that Mr Sunak's alma mater - Winchester College - has a rifle and rowing club, extensive art collection and charges over £45,000 a year in fees for students.
The Labour leader added: "He can carry on being pushed around by the lobbyists, giving away £1.7 billion to private schools every year or we can put that money to good use. End the Tory scandal."
Mr Sunak insisted the Government was "improving school standards for every pupil in this country" and claimed letting private schools retain the exemption was "about supporting aspiration".
Mr Starmer taunted him by reading a quote from a 2017 article by the Levelling Up Secretary Michael Gove, where he said removing the "egregious" tax breaks as one of the best ways of stamping out injustices.
Labour wants to end VAT exemptions for private schools, which the party say would raise £1.6 billion annually.
Shadow Education Secretary Bridget Phillipson told the Mirror: “Governing is about priorities and these VAT giveaways show exactly where Rishi Sunak ’s priorities lie, not in helping every child get a great education but in helping the wealthiest in society.
“Schools are already reeling from a decade of austerity and now headteachers are warning of further cuts to school budgets because his party, the Conservatives, crashed the economy.
“Rishi Sunak says that hard choices need to be made but there is a very simple way that he can invest in our state schools: adopt Labour’s policy and end tax breaks for private schools so that every child gets a brilliant state education."
The Mirror previously revealed that Mr Sunak was set to spend £63,000 on private school fees for his two daughters this year.
The PM's press secretary refused to comment on his children's schooling.
Asked if the Prime Minister thought private schools were better than state schools, she said: "No, I don't think that's his position at all."
She added: "The PM's view is that private schools play an important role in providing opportunities for children around the country and we're providing even more funding for state schools."
Mr Sunak donated £100,000 to his childhood boarding school, Winchester College, earlier this year. The money funds bursaries for children whose parents would otherwise not be able to afford to send them to the school.
