The Finance Minister has warned that a decline in corporate tax revenue "looks increasingly inevitable" in the coming years.
It comes as the Government revealed that tax revenues for the year were over €1.4 billion ahead of target by the end of November.
Corporation tax receipts were ahead of expectations by over €700 million for the same month.
Exchequer returns also show income tax receipts were ahead of target.
Overall, the Department of Finance says overall tax collections have grown by almost €3.5 billion year-on-year - an increase of 6.7%.
Finance Minister Paschal Donohoe said the extra funds will not be used for new spending measures, and instead will help 'build fiscal buffers'.
However, he also said he's aware of the risks of the public finances being over-reliant on corporation tax income - suggesting the high figures "will not last forever".
In a speech earlier today, he explained: "We cannot ignore the clear and present danger of a fall-off in corporation tax receipts.
"The political economy zeitgeist may be changing, but the fundamental duty of any Government to protect the public finances against risks — including those posed by potentially transient corporation tax revenues — has not."
He added: "A further increase for next year is likely but, subsequently, I expect these receipts to begin to fall.
"Building up our surplus is the best way of addressing the decline in corporate tax revenue that looks increasingly inevitable."