Independent schools could be required to raise their fees for the children of wealthy parents in order to subsidise places for pupils from poor families, under new proposals from the Charity Commission.

The recommendation, made today by the commission, is likely to anger parents who scrimp and save in order to afford a private education for their child and who already feel aggrieved at having to pay twice for their education – once through the taxation system for a state-school place they are not taking up and once through school fees.

Matthew Burgess, of the Independent Schools Council (ISC), said the recommendation was tantamount to “surcharging” the middle classes. “Most parents with children at independent schools already feel they are having to pay twice for their child’s education. This is like charging them a third time,” he said.

With average annual fees now more than £10,000 a year, research suggests that the costs have put private education beyond the reach of all but the highest earners.

A survey by the Halifax bank found that only professionals such as judges and chief executives can now “comfortably” afford to pay such fees. Others struggle, often relying on contributions from grandparents.

Today’s recommendation for differential fees is published by the commission in a consultation document on how fee-charging charities such as schools might “earn” their existing tax breaks, which are worth £100 million a year, by providing a public benefit.

The document suggests that schools may seek to offer discounted places to pupils from low-income families by “increasing fees for some beneficiaries to subsidise fees for others who cannot afford the fees”.

Alternatively, it suggests that independent schools can go cap in hand to philanthropists, local authorities and other grant-making bodies, asking them to subsidise more bursaries or scholarships.

The commission said that it would carry out an audit of up to 12 independent schools a year, to verify that they were offering a sufficiently robust public benefit. It emphasised that schools would not simply be able to decide to opt out of charitable status in order to avoid demonstrating a public benefit.

Under charity law, any land assets owned by a charity must be transferred to other charities or to others for use for similar charitable activities or aims.

Jonathan Shephard, chief executive of the ISC, criticised the recommendations, adding that the commission’s interpretation of charity law was so muddled that it would set it on a collision course with the legal profession. “In its current form the draft guidance is heavily biased in favour of wealthier charities, which can fundraise or use endowments to widen access. These charities do a superb job, but are a tiny minority of the charitable estate.

“Most charities – including schools and retirement homes – have little spare cash. Indications from the current draft guidance are that the commission does not fully understand this basic fact,” he said.

The commission says that any public benefit offered by independent schools must not be token or occur by chance, but should be enshrined in the school’s “original purpose”.

Independent schools are also encouraged to back one of the Government’s city academy schools or share their facilities and teachers with state schools or the wider community in a variety of ways.

One innovative example of such charitable outreach was on show yesterday as the City of London School (fees, £12,000 a year) paid for science undergraduates from Oxford to become tutors to GCSE science students at Stepney Green Boys School, a state secondary in East London.

Rob Powell, 19, a chemistry undergraduate from Wadham College, Oxford, who offered his services as a teacher, said: “At the end, one of the boys said he had learnt a lot from me and said I would make a good teacher. It was a really good feeling to think I had helped.”

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