Treasury Minister Alex Allinson says families could pay up to £10,000 a year under a new healthcare levy.
He faced a question for written reply from Ramsey MHK Lawrie Hooper about how the new tax would raise up to £28 million a year to pay for the NHS.
Dr Allinson says the Treasury has worked out estimates where people can earn £14,750 before paying the surcharge, which would then be charged at a rate of 2 per cent.
And he added individuals will pay a maximum of £5,000, while couples face a bill of up to £10,000.
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