The number of children being educated privately has shot past 500,000 for the first time, with more girls opting for boarding school places.
Figures from the Independent Schools Council showed the number of pupils boarding had increased for only the second time in 20 years and now stood at 69,415. The rise was because more than 700 extra girls opted to board (a 2.5 per cent rise). The number of boys fell by 12. Overall, the number of independent school pupils this January topped 500,000.
Independent school heads cited mixed reasons for the increase, including parents' safety fears in allowing their girls to walk to and from inner-city state schools.
Gill Lumsdon, headteacher of Kensington preparatory school in London and chairwoman of the Incorporated Association of Preparatory Schools, said: "Over the past 10 years we've seen an enormous increase in interest in boarding from parents of 11-year-old girls. It's partly to do with security and living in London. They worry about children travelling on their own."
Other heads said the rise was caused by more parents taking the education of their daughters seriously, and the pressures on families as the number of homes with both parents working grew.
Graham Able, Master of Dulwich College, south London, said: "Frankly, parents are now taking boys' and girls' education equally seriously. Sadly, 25 years ago that wasn't the case."
David Woodhead, director of the ISC, added: "It is also possible Harry Potter played a marginal role in making boarding look more attractive. But it seems it's the Harriet Potters rather than the Harrys that have been inspired to board."
Clarissa Farr, head of Queensdown School, Hertfordshire, and chairwoman of the Boarding Schools Association, said perceptions of boarding had changed. Many children boarded less than an hour's drive from their parents' home and saw them at weekends. "The concept of being sent away from home is a thing of the pas. They are being taught in a fulfilled environment, have security and are safe. The increase is particularly amongst parents with busy working lives."
David Hart, general secretary of the National Association of Head Teachers, put the overall rise down to a pupil:teacher ratio of 10.43:1, which was "beyond the wildest dreams of the state sector". He added: "The clear message to the Government is that, unless it produces the goods in the comprehensive spending review, it will again be expecting the state sector to compete with both hands tied behind its back."
The rise was achieved despite an average increase in fees of 7.5 per cent, making the average term fee about £2,600. Heads warned of a further rise of between 5 and 7 per cent this September, blaming increased national insurance costs, levied from next April.
They also said they, too, were feeling the pinch with a drop in the number of applicants for teaching posts. The level of vacancies in the state sector is now almost 5,000.
Mr Able said: "Five years ago, if I advertised for a mathematician, I would get between 30 and 35 applicants. Now it would be around 20."