THE state's wealthiest private schools posted financial surpluses of up to $8.4 million last year after the Commonwealth delivered them as much as $10 million in annual subsidies.

Some did not have to declare their surpluses but the headmaster of Cranbrook School at Bellevue Hill, which topped the list, called for all schools to be as transparent as his and make their finances public.

The King's School

Annual reports lodged with the Australian Securities and Investments Commission for last year show Queenwood School for Girls in Mosman generated a net surplus of $4.7 million after receiving $16.8 million in fees, $1.06 million in donations and $3.2 million in government funding.

Ascham School at Edgecliff recorded a surplus of $3.04 million after receiving $21.6 million in fees and $2.5 million in government funding.