Despite extra money being provided to help cover teacher pay rises, unions warn that schools have had to deal with a £5.4 billion funding shortfall since 2015.
The School Cuts coalition has published an analysis based on school funding figures from 2015 to this year.
The coalition, which includes the National Education Union, the ASCL and the NAHT, says its figures take into account the extra funding provided by government to help pay teacher salary rises.
There’s also been a consideration of the pupil premium and the education funding for 16 to 19-year-olds.
The unions then compared the funding that was allocated for 2018/19 with the budget allocated three years previously.
‘School budgets are at breaking point’
The general secretary of the NAHT, Paul Whiteman, said: “School budgets are at breaking point as school leaders have made the obvious savings. Now the range of subjects schools offer are shrinking and class sizes are rising as they try desperately to balance the books.”
Geoff Barton, the general secretary of the ASCL, said: “Schools have had to make cuts and more are on the way as deficits increase and reserves are drained.
“Budget cut reality is that schools are operating with reduced staff numbers and this impacts on the provision of education with fewer curriculum choices and less additional support for children.
“Schools are in the position of deciding on the least worst option of where they can make cuts or becoming solvent.”
The latest publication by School Cuts comes after they had to defend their previous analysis, which was criticised by the UK Statistics Authority, which highlighted a significant blunder in their report.
Earlier this year, the authority rebuked the coalition for using ‘misleading statistics’ and took issue with a claim made by the unions that 91% of schools are facing a cut in funding.
However, unions say they stand by the claim and have reissued it.
‘We recognise schools are facing budget challenges’
A spokesman for the Department for Education said: “We believe the figures are misleading and while we recognise schools are facing budget challenges, the government has prioritised school funding, taking difficult decisions in other public spending areas to protect school budgets for 5 to 16-year-olds in real terms.”
He added that England’s school funding is now at its highest level ever, and over the last two years every authority in England has been provided with more money for its pupils in every school.