Greater than half of academies in England have lacked sufficient earnings to cowl their annual expenditure, based on figures revealed by ministers.
A solution to a Parliamentary query reveals that the proportion of academy trusts with an annual shortfall doubled in two years.
It comes amid rising warnings about faculty funding shortages.
However Faculties Minister Nick Gibb informed MPs on Tuesday that college funding had been protected and was at document ranges.
The figures have been revealed in response to a query about academy expenditure from the Liberal Democrat peer Lord Storey.
These figures for 2014-15 present that 53% of stand-alone academies had been recorded as having “spent greater than their earnings per 12 months”, up from 42% within the earlier 12 months.
Amongst multi-academy trusts, the proportion spending greater than their earnings was 53%, in contrast with 25% within the earlier 12 months.
This didn’t essentially imply that the academies had been left in deficit – as they may have been utilizing reserves from earlier years.
The ministerial reply says that in 2014-15 solely four% of academy trusts had such a “cumulative deficit”.
However the Liberal Democrats say that it reveals a rising downside with insufficient funding, for academies in addition to native authority faculties.
“Academies are already falling in need of money and this a deep concern to workers and oldsters. It reveals that the system that the Conservatives have created has a shaky basis,” mentioned Liberal Democrat training spokesman John Pugh.
“The federal government wish to fake that academies and free faculties are the reply to the funding issues however this reveals that they are not proof against the impression of the federal government slashing training budgets,” he mentioned.
College leaders have been more and more vocal in considerations about funding ranges.
Head lecturers have been warning about having to chop faculty hours, governors have threatened to refuse to log off budgets and grammar faculty leaders have mentioned they may have to begin charging mother and father.
Final week, heads had been angered when it was revealed that £384m earmarked for changing faculties into academies final 12 months had been taken again by the Treasury.
On Tuesday, Nick Gibb, minister for college requirements, confronted questions from the training choose committee on faculty funding.
He rejected options of underfunding for faculties and informed MPs that the federal government had “protected funding at a time after we are coping with an historic price range deficit”.
Mr Gibb mentioned faculties had been receiving greater than ever earlier than – and that this might rise with an additional enhance within the faculty inhabitants.
The best way that college funding is shared out to particular person faculties can also be being modified – with the launch of a brand new funding formulation.
The colleges minister mentioned that the federal government had “grasped the nettle” on needing to reform a funding system that was typically uneven and unfair.
However there was no “silver bullet” on faculty funding, he mentioned, and switching to a brand new formulation would imply winners and losers.