There are 17,942 schools that will experience budgets cut because of the government’s funding plans, a coalition of unions has claimed.

Just days before the Budget, the unions responsible for the School Cuts website - the NEU teaching union, the NAHT headteachers’ union, Unison, Unite and GMB - have updated their data.

According to their calculations, which are based on Department for Education figures, 17,942 schools are facing real terms cuts in per-pupil funding.

This is 500 more than originally predicted and represents nine out of 10 schools.

In the House of Commons earlier this month, Justine Greening described the School Cuts website as inaccurate and “scaremongering”.

Responding to that claim, the unions said they were being “completely open about their figures and methodology”.

“Many other groups, including parents, school governors, and a delegation of more than 5,000 headteachers have been arguing for some time that school budgets are at breaking point,” they said. “The school funding crisis is real.”

The unions added: “While the extra £1.3 billion, which the DfE is reallocating from its existing budget, is welcome, it is short of what schools need if standards are to be preserved. Only a fully-funded education system will deliver the equality of opportunity that school staff, parents, governors, school leaders and politicians are all so passionate about.”

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