In the past academic year, academies received state funding of just over Pounds 9,000 per pupil, while top independent day schools - members of associations such as the Headmasters' and Headmistresses' Conference - received an average pound;9,100 in fees per pupil.
But the Department for Education and Skills denied that academies received especially generous funding. A spokesman said they were paid recurrent grants on the same basis as their state neighbours. "Fact - academies do not receive any more funding than other schools," he said. "We have always been clear that there must be parity of per-pupil funding with schools in the maintained sector that operate in similar circumstances."
Tony Blair this week took credit for academies, telling The TES that they had been his idea. Meanwhile the Conservatives pledged to push the programme "further and faster" saying they believed academies rather than grammar schools were best to raise standards.
But grants handed to academies by the department were so generous that they received almost pound;1,600 more per pupil on average than neighbouring comprehensives. The average funding for non-academies in similar circumstances was just under pound;4,900 a year, while academies netted just under Pounds 6,500 on average.
The TES analysis was based on the 2005-06 accounts of 14 operational academies that filed information at Companies House.
Possible explanations for the funding disparity could include the compensation that academies receive because they are liable to pay VAT and for local authority services. But this would not explain the whole difference. Start-up costs for academies, which were identified in the accounts, were factored out.
John Dunford, general secretary of the Association of School and College Leaders, whose members include academy heads, said the findings showed a need for greater clarity over the way local comprehensives are funded.
"Academies are becoming part of the local family of schools," he said.
"This makes it all the more important that there should be a level playing field between them and other schools. We need a funding formula that recognises the mountain that all academies have to climb, but which is in proportion to their need."
David Willetts, shadow education secretary, said the Conservatives would drop the requirement for sponsors to contribute pound;2 million and would allow them to sign a single contract for as many as 20 academies.
The financial contribution had "caught up academies in the mire of the cash-for-honours scandal", he said, and was preventing educational charities and other sponsors from becoming involved.
Academies cash in, page 18