Tax and Duty Manual Part 41A-05-04 – Full Self-Assessment: Time limits for making enquiries and raising assessments – is amended in Paragraph 4 to clarify the circumstances where assessments can be amended and to confirm that assessments can be made or amended outside the four-year timeframe on conclusion of a Mutual Agreement Procedure, as provided for in section 959AA(2A) TCA 1997.

Revenue cannot make or amend an assessment on a chargeable person who delivered a full and true return later than four years after the end of the chargeable period in which the return is filed, meaning that no additional tax can be payable and no tax can be repayable after this time. However, at any time, Revenue can amend an assessment:

• where the return was not a full and true disclosure;
• to give effect to the determination of an appeal;
• to reflect an event which happened after the return is filed;
• to correct a calculation error in the assessment;
• to correct any mistake of fact which was disclosed by the taxpayer and not correctly reflected in the assessment; or
• to give effect to bilateral Mutual Agreement Procedures reached between Revenue and a competent authority in another jurisdiction with which Ireland has a Double Taxation Agreement.

See Revenue eBrief No. 145/21 for more details.