A 201-year-old boarding school near Hitchin is set to close in the summer after concerns were raised over its current and historic financial position.
The historic Princess Helena College, a co-educational day and boarding school in Preston, will close at the end of this academic year on August 31.
In a letter addressed to parents, Sir Jon Coles, chief executive at United Learning, explained it had been "impossible to make the school financially viable or to successfully identify a buyer".
He continued: "We are all extremely disappointed that, despite everyone’s best efforts, it has not been possible to create a sustainable future for PHC.
"This decision is neither a judgement on the school itself, nor on its leadership or track record.
"It is purely a reflection of its historic and current financial problems and the ongoing economic impact of the pandemic on current and future demand for places.
"We appreciate that this will be both a shock and a disappointment to everyone across the school community. It is not a decision that we have taken without exhausting all other options."
United Learning was approached by PHC's governors in 2018, and they say that without their subsidised investment of £3.1 million over the last three years, the school would have closed.
Potential buyers had been mooted and discussions had initially been promising, but these all amounted to nothing substantial.
United Learning says it will support parents in helping them find new educational provision for their children by September.
A spokesman for United Learning added: "The school has faced financial difficulties for many years. These have been significantly exacerbated by the impact of COVID-19 on the local and international demand for places at the school.
"Despite everyone’s best efforts, all options for keeping it open have been exhausted and, regrettably, the school will close later this year.
"We are doing everything we can over the next few months to assist families in identifying places elsewhere for their children for September."
The school was formed in 1820, for the daughters of Anglican clergy and officers who had served during the Napoleonic Wars.
It moved from London to its current site in Hertfordshire in 1935.
PHC has shared a close relationship with the Royal Family since the 19th century, with Birgitte, Duchess of Gloucester serving as the school's current president.
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