FEE-paying schools here have an average of €1.5m each to spend a year on extras for their pupils, a Department of Education report has revealed.
Ireland's 55 private secondary schools can use the money to recruit more teachers and other staff, lay on extra-curricular activities and build facilities.
Because the sum is an average, it's been revealed some of the fee-paying schools have much more than the €1.5m discretionary spending – one large school has €4.7m to spend a year.
At the other end of the scale, a relatively small private school has €112,000.
In total, the sector enjoys an €81m revenue boost over and above that available to similarly sized schools in the free education scheme.
Because of its confidential nature, the report does not identify any schools, but it reveals that nine charging in excess of €6,000 a year have an average €2.2m in discretionary income.
At the lowest fee level category, there are seven schools charging €2,500-€3,000, with an average discretionary income of €696,000.
Overall, two-thirds of schools have in excess of €1m a year, while more than a quarter have over €2m to spare.
The additional funding works out at an average of €3,177 per student over and above what a similar sized school in the free education scheme has to spend.
If the average school was to use the money to employ extra teachers, it would allow for about 20 additional staff.
Education Minister Ruairi Quinn sought the report to guide future policy decisions about the extent of state funding to fee-charging schools. A spokesperson for Mr Quinn said the purpose of releasing it now was to inform debate on the issue.
The latest revelations will ignite the debate about withdrawing the state subvention for fee-paying schools. Labour TD for Dublin South West Eamon Moloney reacted immediately and said the "bailout" of fee-paying schools must end.
"Parents who wish to avail of private schools are entitled to do so, but the taxpayer should not have to subsidise the privileges that private schools offer," he said.
The department's analysis refers to the ongoing budgetary difficulties and states that "the extent to which teaching posts can continue to be allocated to fee-charging schools must remain under consideration".
The analysis found that the schools bring in €117m a year in fees, but this was reduced by over €35m when account of repayment on capital loans, uncollected fees and fee discounts were taken into account.
The analysis was based on fee income in 2012 and on figures provided by the schools. Tuition fees charged by the schools range from €2,550 to €10,065.
The State pays about €96m a year in subventions to fee-paying schools, mainly in the form of teachers' salaries.
The sector has seen a gradual reduction in state support in recent years because of pressure on two fronts – saving money and introducing more equity into education.
Arising from the last Budget, the pupil-teacher ratio in fee-paying schools will rise from 21:1 to 23:1 in September, compared with 19:1 for those in the free education scheme.
According to the report, even if the pupil teacher ratio in fee-paying schools went to 28:1, as recommended in the Bord Snip report, the schools would still have €62m to play around with.
Ongoing cuts, and uncertainty about what will happen in the future, is causing anxiety among schools at the lower end of the income range, many of which are Protestant.