Fianna Fáil is calling on the Government to clarify why some highly paid civil servants will be paying significantly less in PRSI in January, compared to ordinary workers.
In a parliamentary reply to Deputy Michael McGrath, Minister Joan Burton confirmed that public servants who were recruited before 1995, will pay as little as €12 per year in PRSI in January.
All other workers earning more than €18,500 will pay an extra €264 per year.
Deputy McGrath said the disparity was grossly unfair and had to be changed.
"There is a favourable PRSI regime in place for people who were recruited into the public service pre-1995," he said.
"Essentially on incomes up to €75,000 per year they only pay 0.9% PRSI, whereas an ordinary worker in the private sector, and anyone in the public sector since 1995, is paying 4%.
"It's a gross injustice and an anomaly that people would want to see addressed."