Hard-hitting levies from Budget 2011 have pushed the Government's tax take €607 million (£545m) ahead of last year's figures.
Exchequer figures show the country's finances €9.9 billion (£8.9 billion) in the red for the first three months of the year and in line with official expectations.
But with the Universal Social Charge and other reforms the tax take is €108m (£97m) or 1.1% ahead of profile at end-April, the Department of Finance said.
The budget deficit for the same period last year was just under seven billion euro (£6.2 billion) in the first four months of 2010.
The Department said it will continue to monitor the data on tax returns closely and will present a view on the likely outturn for the year in early July.
Officials said that three of the "big four" tax heads - income, corporation and excise duties - outperformed their targets in the first four months of the year.
VAT was €107 million (£97m) or about 3% behind target at the end of April due to a relatively poor performance in February.
Elsewhere, the Department said there had been an earlier than expected payment of receipts from Deposit Interest Retention TaxReuse content