MANY of Sydney's most prestigious private schools posted multimillion-dollar profits last year, with their financial positions greatly enhanced by federal and state funding.

Profits ranged from $1.6 million at Kesser Torah (government funding $5.6 million) to $7.3 million at Cranbrook (government funding $5.3 million). None of the schools reporting results posted a loss.

Loreto Kirribilli had the biggest surplus, $12.9 million. The unusual result - last year's surplus was $1.2 million - resulted from the transfer of $11 million from the Loreto building and education trusts to buy a neighbouring property.

Another school in the property market was Ascham, which recently bought a Darling Point mansion for $12.25 million and posted a surplus of $3 million.

The principal of Loreto, Janet Freeman, said 11 classrooms would be built on the new site, enabling expanded facilities for students with mild to moderate intellectual disabilities.