St Margaret's in Edinburgh's Newington will now close on Tuesday after a buyer to take over the school could not be found. It is understood bids have been made for the nursery but a fund-raising campaign failed to collect enough to save the primary and secondary.
Val Devlin, a spokeswoman for the St Margaret's Parents and Friends Association, last night admitted the group was ending its campaign. She said: "There just wasn't enough time to find 2.5 million."
Parents yesterday morning met liquidators, KPMG, to discuss the prospects for saving the school. The decision to end the fundraising campaign was taken following the meeting.
Ms Devlin said: "They couldn't give a great deal away to us but they kept asking what they could do to help people if the school couldn't be saved.
"Nursery bids are being considered and will have to go through due diligence, so that aspect of the school is secure.
"As far as the primary and senior schools are concerned, there was just not enough time to get up and running by August."
The decision to end the fund-raising campaign was made to allow parents to take up places at other schools next year.
Ms Devlin added: "Parents were looking for a clear yes or no before they accepted places offered at other schools across Edinburgh.
"We pulled out every single stop. If we had been spoken to before the liquidator was requested, we are confident we would not be in this position now."
And she added: "St Margaret's will close on 29 June and won't reopen – after 119 years of history.
"For the first time I have been crying; we have not rested since the news broke, but now we need time to grieve.
"It's a clich, but the school really is like a big family. I feel sorry for all the girls who will not now experience a St Margaret's education."
A consortium of ten families had hoped to take over the running of the all-through school which takes nursery children up to sixth year. They hoped to raise more than 2m to pay off the school's creditors and create a trust with parents as governors.
However, the group had failed to attract a "white knight" investor by their own deadline of 5pm last Tuesday.
Earlier this week, it emerged only 100,000 had been raised in donations after the campaign pleaded with former pupils and "friends" of the school to come to its rescue.
It's understood the school, which had a roll of around 367 pupils, has considerable debts, which may have proved a deterrent to potential investors.
HM Revenue & Customs and the Royal Bank of Scotland are understood to be major creditors left out of pocket after the school's governors called in the liquidators last month.
The headmistress, Jennifer McGhee, wrote to teachers earlier this month advising them of the closure which is likely to result in up to 140 job losses.
Ms McGhee said the decision had been made at that particular time, to ensure the pupils' exams had finished.
Parents are also likely to be out of pocket after paying next year's fees, of up to 15,000 a year for boarders, in advance.
Judith Sischy, director of the Scottish Council of Independent Schools, praised the parents for their campaign.
She said: "It was courageous of the parents to try to save the school."
"It would have been wonderful if they could have raised the money but I think they did all they could in the circumstances."