S.L. 123.204 Art. 4Tax rebate. 

In the case of an individual who, in the year of assessment 2027 or any subsequent year, benefits from the exemption granted under rule 3 and who is chargeable to tax at the rates specified in article 56(1)(a)(i) of the Act, a tax rebate shall be granted as a set-off against the tax on the chargeable income, as follows: Tax rebate = (chargeable income less 15,000) multiplied by 15%:

Provided that such rebate shall not exceed €540:

Provided further that any negative result shall not be taken into account and any rebate granted under this rule may not give rise to a refund or be available to be carried forward.