That's according to new research from the ESRI.
It expects costs to rise by 5% per year over the next 15 years, with pay costs the single biggest factor behind the increase.
Demographic changes will also see demand for public hospital care go up by about 1.5% per year over the same period.
Conor Keegan from the ESRI says the cost of reducing long waiting lists to 12 weeks over the coming years will also be significant:
"Incorporating these recent effects of COVID we estimate that to tackle the existing backlogs and to achieve this reduction in waiting times within five years would cost approximately €200 million per year, or €1.1 billion over five years, so to contextualise that around 3% or 4% of gross public hospital expenditure per year."
