Parents told to pay higher fees at an elite prep school to cover salary rises were angered to discover that teachers’ pay had actually been frozen.

In a letter to parents at the £18,000-a-year Mowden Hall School in Northumberland, seen by The Times, the bursar said that an increase in fees this term was unavoidable because of contractually binding rises in staff costs.

“Seventy per cent of our costs are in salaries. Over this we have little control, and the teachers’ awards declared by the Government are 2.3 per cent in September,” Simon Blackmore said. Fees were then increased by 2.8 per cent.

But in separate correspondence, Mr Blackmore told teachers that the “current financial climate” prevented the school from increasing salaries.

“It has been decided to maintain present levels of pay until there is evidence of an economic upturn,” he wrote three months after contacting parents.

The situation is symptomatic of the struggling private school sector. Small prep schools are under financial strain and many have closed in the recession.

However, parents have been highly critical of the move by Mowden Hall. “It is despicable. If they say they are going to do something, they should do it,” said one parent, who wished to remain anonymous. “They should either put up staff salaries, or cut fees,” she added.

Dwindling numbers at the school, where the headcount is believed to have fallen by 16 per cent since 2007, are thought to be behind its action.

The school has also been accused by some parents of inflating its numbers in published documents. Information provided by the school to the Independent Schools Directory states that Mowden Hall has more than 220 pupils in 2009-10. But numbers are said to be much lower, at 164, across the nursery, pre-prep and prep departments.

The co-educational school for children aged 3 to 13 was taken over by Cothill Educational Trust in 2007 to gain financial security, but there are claims that it has suffered falling rolls and adverse economic conditions. A source close to the school said it was probably running at a loss: “They have got themselves into a very difficult position.”

Teachers are believed to be unable to turn to their union over the issue because they accepted the pay freeze before they knew that fees were going up.

Ben Beardmore-Gray, the headmaster, says on the school’s website that Mowden Hall “gives children a rounded and broad education in which each discovers their talents and fulfils their potential”.

Larger independent senior schools are also suffering with hundreds of pupils withdrawn. Prep schools have increased fees by 2.95 per cent on average this year, according to a survey by the Independent Association of Prep Schools. At top public schools, parents are paying an extra 3.4 per cent on average.

No one at Mowden Hall or Cothill Education Trust was available for comment.

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