A report published today has said the Commission to Inquire into Child Abuse is expected to cost the State between €126 and €136m, if it completes its work by the end of next year.
The report by the Comptroller and Auditor General also said the Commission was originally given two years to complete its work, at a cost of between €1.9 and €2.5m.
However the Commission, which published its findings in May, took more than ten years to complete its work.
Legal fees contributed to a significant proportion of the costs. The Commission's most recent figures suggested that the final costs of third-party representation could be between €52m and €62m.
The report also estimated that administration costs will amount to €30m, while the commission's legal team will cost almost €16m.
It said some support work was done using counsel when less expensive staff could have been used.