Schools in Cumbria face being hit with a £23m funding cut, headteachers claim.

The National Association of Head Teachers (NAHT) has warned Cumbria could be a facing the huge real-terms shortfall in its schools budget by 2020.

The NAHT claims the money lost in Cumbria will be equivalent to £383 per pupil or 625 teachers – and has warned it could lead to increased class sizes in primary schools. Some GCSE and A level subjects could also be cut from the curriculum.

Their warning comes with stage two of the Government’s schools national funding formula currently under consultation. The Department for Education insists the predictions made by both the NAHT and National Union of Teachers (NUT) are incorrect and the money provided to schools across Cumbria will actually increase by 1.4 per cent under the proposals.

Figures published by the Department for Education state the local authority total

baseline for schools, high needs and central school services blocks currently stands at £314,862,714.

The DfE says that this would increase by more than £4.3m to £319,166,119 should the new funding formula be accepted.

But Graham Frost, headteacher of Carlisle’s Robert Ferguson School and Cumbria branch secretary of the NAHT, says real-term costs are not taken into account.

He said: “They’re keeping the funding allocation per pupil the same, but what they’re not taking into account is that we’ve had a 5.5 per cent increase in our contribution to starting costs, which include national insurance and pensions. A large part of our budget – 80 to 90 per cent – goes on staffing and they’re talking about funding per pupil, when we’re talking about real-term costs. It feels like the Government wants an education system which fills the budget they’ve set out, rather than taking into account what’s needed.”

Workington’s Labour MP Sue Hayman said the potential cuts would have “a real impact on Cumbrian children being able to achieve their potential”.

She said: “The new formula would see nearly half of English schools losing money in a process that merely moves money around the system rather than providing additional crucial investment in schools. Schools have already had to make cutbacks – in order to make further savings, many will now have to start cutting teaching staff. It’s time we had proper investment in our schools, so they can replace crumbling buildings and give our children the high-quality education they deserve.”

Liberal Democrat leader and Westmorland and Lonsdale MP Tim Farron has tabled a motion for Cumbrian schools’ funding to be discussed in Parliament.

A DfE spokesperson said: “The union’s figures are fundamentally misleading. School funding is at its highest level on record and will be over £40bn in 2016-17. Over the last six years we have seen the number of children being taught in schools that are rated good or outstanding rise by more than 1.8m. The unions ignore the fact we are protecting per pupil funding so where pupil numbers rise, the amount of money schools receive will increase. The government has protected the core schools budget in real terms since 2010, but the system for distributing that funding across the country is unfair, opaque and outdated.”