The final cost of the compensation schemes for victims of abuse in religious institutions is expected to hit almost €1.5bn.
Although applications to the scheme stopped nine years ago, the cases are still being processed by the Residential Institutions Redress Board.
The average payout to victims is €62,860.
Last year, the bill for the redress scheme hit €903.8m, with legal costs of €166.1m.
The final cost is predicted to be €1.46bn.
If the costs were to be split 50/50 between the State and the religious institutions, the religious orders would have to pay €730m.
But a Government spokesperson said the contributions offered so far "fall well short".