State school budgets in England have deteriorated in the last year, according to analysis by a thinktank that says councils could redistribute surpluses to bail out struggling schools in the same region.
The Education Policy Institute looked at the accounts submitted by maintained and academy schools for 2017-18 and found that secondary schools were particularly hard hit.
According to the EPI, half of all secondary academies and 60% of maintained secondary schools ??? those managed by local authorities ??? are spending more than they are receiving, forcing them to dip into their reserves.
Jules White, head of a secondary school in West Sussex and a founder of the WorthLess? campaign for fairer funding, said: ???Time and time again, independent analysts are confirming what every headteacher in the country knows; schools are sliding further and further into debt, regardless of whether they are local authority or academy controlled.
???No doubt the Department for Education will bury its head in the sand again and trot out all of the usual smokescreens regarding efficiencies and surpluses, yet on the ground headteachers continue to cut staffing, their curricular offer and crucial pastoral services in order to make ends meet.???
In a worrying sign, the EPI also said the proportion of local authority special schools in deficit has doubled from 5% to 10% since 2014.
???These findings are further evidence of the funding pressures schools and councils are under, including support for children with special needs,??? said Anntoinette Bramble, chair of the Local Government Association???s children and young people board.
But while schools budgets had worsened in the space of a year, the EPI said that many still had strong bank balances, and that overall the value of surpluses exceeded that of the combined deficits.
In 2017-18, local authority school deficits totalled ??233m, while the total of surplus balances was ??1.8bn, of which ??580m met the DfE???s ???excessive balance??? definition.
???In fact, by the Department for Education???s definition, nearly a quarter of a billion pounds is in accounts deemed excessive and uncommitted to any specific expenditure. The challenge for government, local authorities and school leaders is whether that money should now be redistributed,??? said Jon Andrews, the report???s author and deputy head of research at the EPI.
???In practice, over half of the ???excessive??? balances are already committed by the schools to specific projects, and given the priority which the government attaches to school autonomy, there would likely be serious policy challenges involved in trying to reallocate such surpluses,??? the EPI said.
The EPI???s suggestion drew a tepid response from school leaders, with Geoff Barton, general secretary of the Association of Schools and College Leaders, arguing that it was ???prudent financial management??? for schools to have surpluses.
???What is clear is that the current trend is one of increasing deficits and unless action is taken to improve the level of funding it is highly likely that educational standards will deteriorate,??? said Barton.
A DfE spokesperson said that more than 90% of academies and maintained schools had broken even or were in surplus last year.
???Whilst the core schools and high needs budget is rising from almost ??41bn in 2017-18 to ??43.5bn by 2019-20, we do recognise the budgeting challenges schools face.
???That is why the education secretary has set out his determination to work with the sector to help schools reduce the ??10bn they spend on non-staffing costs and ensure every pound is spent as effectively as possible to give children a great education,??? the DfE said.
Angela Rayner, the shadow education secretary, said the government was refusing to accept that it had caused the funding crisis.
???These cuts have made it impossible for many schools to even make ends meet, and there will be a generation of children paying the price for the Conservatives??? failure,??? Rayner said.