Many schools could be sent over the edge financially after spending thousands of pounds on keeping sites Covid-secure, headteachers have warned.

Paul Whiteman, general secretary of the NAHT school leaders’ union, said it was “baffling” that the government was refusing to provide schools with financial support for additional Covid-19 costs this term.

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In just the few weeks since the beginning of term, schools in England have spent an average of £8,017 on additional costs to minimise the risks of Covid-19, which have included enhanced cleaning supplies, personal protective equipment (PPE) and hand-washing stations, a survey by the union shows.

The NAHT survey, of more than 2,000 school leaders in England, shows that schools have already lost an average of £9,755 in income this term alone as restrictions have led to a drop in demand for renting out school facilities.

Coronavirus: The impact on school funding

The findings come ahead of the NAHT’s virtual conference, where delegates will debate a motion that instructs the union to “use all means at our disposal to secure adequate funding for all our schools”.

Previous data from the union showed that, between March and September, schools had spent an average of £9,990 on Covid safety measures and faced lost income of £15,915.

The new survey suggests that financial pressures on schools are mounting.

There has been a 17 percentage point increase in heads reporting that they are incurring, or expect to incur, additional staff costs for teaching assistant time, compared with when the union asked heads about additional costs.

The findings also suggest there has been a 10 percentage point increase in school leaders experiencing additional costs for cleaners or site staff.

The government originally suggested it would cover the additional costs schools faced in the summer term, but the NAHT poll suggests that nearly three in four (73 per cent) of schools have not received any of the exceptional costs funding announced by the Department for Education.

Of those that had received money, more than half (52 per cent) said it had reimbursed less than half of their additional expenditure due to Covid.

Mr Whiteman said: “These costs are not optional for schools. They are required by the government’s own guidance.

“Schools need the government to make good these unanticipated but necessary costs in order to protect school budgets so that pupils’ education is not adversely affected.

“It is frankly baffling that, despite this, the government is refusing to provide schools with any financial support when it comes to Covid costs this term.”

He added: “School budgets for this year were allocated prior to the outbreak of Covid-19 and so did not take into account the additional spending required.

“This means that every pound spent on new safety measures is a pound that can no longer be spent on pupils’ education.

“Not only will this potentially eat into any ‘catch-up’ funds schools receive, but it could push many into a deficit position.

“School budgets were under huge pressure already and this could be enough to send many over the edge.

“Schools are now facing the possibility of these costs spiralling as we move into the winter months ahead.”

Previously, heads have raised concerns over whether they can provide catch-up learning, having been forced to use government funds to plug holes in school finances left by implementing Covid safety measures.