Brent schools are among the most “at risk” of losing out in the government’s National Funding Formula, according to predicted data.

Described as an “historic reform” by former education secretary Justine Greening, the formula, which comes into affect this month, sees an increase in spending on schools nationally by £1.3 billion over the next two years.

But education unions have been at pains to point out that the majority of schools are still running at a deficit longer term. According to their figures – based on government data and Institute for Fiscal Studies calculations – Brent schools will have lost £14.9M between 2015 and 2020.

This is the equivalent of losing £372 per pupil over the same period, a rate which is the third worst in London.

The schools predicted to experience the biggest funding pinch in the period between 2015 and 2020 are Wembley High Technology College (-£820,110), Kingsbury High School (-£832,971) and Preston Manor School (-£834,320).

Wembley High was named earlier named by the Department for Education as one of the highest performing schools in the country in its published league tables for secondaries earlier this year.

Most of the schools losing out the most – due to the number of pupils catered for – are secondaries, but Lyon Park Primary School has been earmarked as losing £765,756 over the five year period.

Paul Whiteman, general secretary of school leaders’ union of the National Association of Head Teachers (NAHT), said: “We desperately need the government to recognise that overall funding for schools is insufficient.

“It is totally unrealistic to ask school leaders to plan efficiently and effectively for the long term if they have no information about what will happen in as little as two years’ time. All schools need significant increases in funding. And as they fail to materialise, some school leaders could believe that the formula is the problem.”

The two key factors behind the union’s calculations are government cash being reallocated across the country and funding not rising with inflation.

According to the data, all 70 schools in Brent are facing cuts, with Carlton Vale Infant School (-£1,493) and Malorees Junior School (-£5,215) earmarked to lose out the least over the five-year period.

To check how your school will be affected by budget cuts, visit schoolcuts.org.uk.