Tax Controversy

New measures not announced in Budget 2026

Finance Bill 2025 contains a number of amendments to Revenue’s powers which will have tax administration implications for taxpayers, including the following:

• Section 31 introduces a new Section 959AX TCA 1997, which gives Revenue the authority to estimate corporate and income tax liabilities when a taxpayer fails to file the required tax return. This new provision mirrors the existing VAT estimation process. For income tax and corporation tax the estimated figure will be based on the average amount of tax due on the 2 most recent returns, or €1,000, whichever is higher. 
• Section 90 enhances powers for Irish Revenue officers to combat tax avoidance. Under the General Anti Avoidance Rules contained in Section 811C TCA 1997, Revenue can deny or withdraw tax advantages arising from tax avoidance transactions where a taxpayer has submitted a return, declaration, statement, claim or account. This amendment extends Revenue’s authority to withdraw that tax advantage where it has arisen from any other action or lack of action on the part of the taxpayer.
• Finance Bill 2025 also clarifies tax due dates, and consequent calculation of statutory interest, in circumstances where an assessment has been amended more than once. Section 97 amends Section 959AU TCA 1997 and states that where an assessment is amended more than once, the due date for paying any additional tax from the second or subsequent assessment is determined independently from the original or first amended assessment – which could lead to an earlier due date/deemed due date of payment of tax depending on the amount of preliminary tax paid.
• Section 95 extends Revenue’s powers to make or amend a tax assessment outside the usual four-year time limit to implement a Mutual Agreement Procedure (MAP) reached under a Tax Information Exchange Agreement. This amendment aligns with existing rules which already permit such extended assessment where a MAP is reached under a double taxation agreement.

Who will be affected and when?

Individuals and corporation tax filers will be impacted by these amendments. Significantly, where no tax return is filed, taxpayers may receive an assessment, or multiple assessments, to tax based on an estimate from Revenue. Without further action on the part of the taxpayer, this tax liability may accrue interest and penalties and may result in enforcement proceedings on the part of Revenue.

What now?

With the changes introduced in Finance Bill 2025, including the expansion of Revenue’s powers, to revise assessment timelines, withdraw or deny tax advantages and the new tax liability estimation rules, it is essential that taxpayers take stock of their tax affairs and consider their compliance with registration, filings and payment obligations.

The Finance Bill demonstrates that transparency and compliance are of upmost importance to Revenue. We would encourage taxpayers to ensure that all required tax returns represent a full and true disclosure of all material facts necessary and are filed in a timely manner, along with payment of the related liability.

Adherence to these expanded rules and engagement with your tax agent would be recommended with a view to avoiding additional interest/penalty exposures and increased risk of intervention activity from Revenue.

Our view

It is clear from these updates that Revenue is tightening its approach to tax compliance, strengthening its ability to act on non-compliance and thus placing more onus with taxpayers to ensure compliance with registration, filing and payment obligations.

It will be interesting to see how Revenue leverages these increased powers under General Anti Avoidance Rules.