Thousands of children face missing out on all their chosen primary schools next week amid a snowballing crisis over places.

Councils are struggling to cater for rising pupil numbers, fuelled by a baby boom and high immigration.

As a result more than 20,000 youngsters could be denied a place at all of the schools listed on their applications this year.

It will mean ‘significant numbers’ forced to travel long distances to schools in other areas, experts have warned.

Thousands of children face missing out on all their chosen primary schools next week amid a crisis over places. File photo

Many local authorities have had to create classrooms in disused buildings, build extensions to schools and add ‘bulge’ classes to cope with the extra demand.

More than 600,000 children are set to receive their primary places for September on national offers day this Thursday.

Matt Richards, senior partner at consultants Schoolappeals.com, which helps families challenge admissions decisions, said he had already received calls from worried parents.

‘It’s highly likely there will be a significant number of parents that won’t have a place in any school this year, let alone a preferred school,’ he said. ‘They will be told to travel very large distances – two or more miles – to areas where there is less demand. In a city like London, this could take over an hour and a half.’

Alan Smithers, professor of education at the University of Buckingham, said pupil numbers had been boosted by generous benefits, immigration and career women having children later in life. He added: ‘We have had unbridled immigration and many of the people who have arrived have had much larger families.’

Last year, almost 77,000 children failed to secure a place at their first choice primary school.

More than 22,400 missed out on all the primaries they applied to and were allocated an alternative on offers day, while 3,700 initially failed to get a state school place at all. Hundreds were still waiting last summer as councils scrambled to find extra places.

Councils are struggling to cater for rising pupil numbers, fuelled by a baby boom and high immigration. File photo

Local Government Association (LGA) projections suggest the pressure will be worse this year, saying that for the first time, one in five council areas in England will have more children ready to start school than available places.

It predicted London would be squeezed hardest, with the most oversubscribed borough of Harrow receiving 112 applications for every 100 places.

Earlier this year, Oxford University research found London had seen a significant increase in immigration over the last four years, with its migrant population rising 6 per cent from 2,998,000 in 2011 to 3,187,000 in 2014.

Outside London, Bristol, Leicester and Slough will also reach ‘tipping point’, the LGA said. Last year, it predicted 130,000 extra primary places will be needed by 2017 – around 4,750 new classes or 500 schools.

Councils responding to a Daily Mail survey admitted having to bring in emergency measures this year. Those in Northumberland, York and Bolton had added extra classrooms, while Poole council in Dorset built a new school.