The UK needs more low-cost boarding schools so that parents with modest incomes can afford the fees, Tony Little, the former head of Eton College has said.
Large fees at many top schools are putting parents off and the sector would benefit from a much wider range of options, he argued.
Mr Little, who is president of the Boarding Schools' Association (BSA), said cost was a "huge issue" for families, with private boarding fees reaching £35,000 a year.
A key problem was that all boarding schools wanted to be the kind that have "two dozen sports and nine modern languages and all the rest of it", he added.
"There is a place for a more affordable option, offering a really good-quality boarding experience but with perhaps less of a range of things on offer," he told reporters at the annual gathering of the Headmasters' and Headmistresses' Conference (HMC) in St Andrews. "The costs are being driven ever upwards and it is an issue for the boarding sector as a whole to face.
"What we need are more levels in between and I think that is something for the boarding system to address."
Figures from the Independent Schools Council (ISC) show that the overseas market for boarders is flourishing, with foreign parents frequently more able to pay the fees than domestic ones.
There are more than 27,000 non-British pupils whose parents live overseas in ISC schools this year – representing just over 5 per cent of the total pupil population.
Mr Little said that he expected to see more state boarding schools in the UK, adding: "There is a very strong and special tradition in British boarding. We do have something quite remarkable, I believe, in this country, and it's mirrored in the state boarding school sector as well.”
Eton College is a backer of Holyport College, a state boarding school in Berkshire.