The Council of Trade Unions estimates an extra $500 million at least is needed in the Budget on 20 May to keep the health system at its current level.
Last year, health received $750 million in new spending and the Minister of Health has been clear that the increase will be smaller this year.
The CTU says its analysis of health expenditure shows the budget will need to be increased by at least $555 million to keep the system in its current state.
CTU economist Bill Rosenberg says a larger increase in funding is required if problems such as district health boards deficits and loss of services, are to be addressed.
