Blanchelande, Elizabeth and The Ladies’ College have reacted to plans to gradually phase out their States' funding.
A Policy Letter which proposes the phased removal of financial support for Guernsey's private colleges will be published on Monday (17 February).
The States grant will be worth £2.8M next year.
The Education Committee (ESC) says this is 'not the best use of taxpayer money' and does not promote equality.
The three colleges disagree and have released a joint statement explaining why they believe the financial support ‘should continue at its current level’.
They argue they form a significant part of the island’s education ecosystem, educating around 30% of secondary school pupils for around 3% of the education department's budget.
They note around 30% to 37% of the children in each college are from less well-off families, and 34% to 39% have special educational needs.
They say while they 'recognise the States’ financial position' stopping their grant will not result in 'sustainable saving' because 'children cannot be accommodated into the States’ sector without additional cost.'
They warn families and businesses may choose to move away from Guernsey if the funding arrangements change; destabilising the economy and reducing competitiveness.
They say Jersey, Australia, New Zealand and the USA all subsidise independent schools.

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