How to Appeal a Capital Gains Tax Assessment in Ireland (2026 Guide)
Disposals of property, shares or other assets can trigger a Capital Gains Tax assessment you disagree with — often over the valuation used, the base cost allowed, or whether a relief such as Principal Private Residence Relief applies. These assessments are appealable to the Tax Appeals Commission under Part 40A of the Taxes Consolidation Act 1997.
The 30-day deadline is strict. Under section 949I TCA 1997, your notice of appeal must reach the Tax Appeals Commission within 30 days of the date on Revenue's notice of assessment.
Common Reasons to Appeal a CGT Assessment
- Disputed market valuation — Revenue's valuation of the disposed asset differs from yours
- Base cost disputes — acquisition cost, enhancement expenditure or indexation not correctly applied
- Relief refused — Principal Private Residence Relief, Retirement Relief or Entrepreneur Relief not allowed
- Loss relief disputes — capital losses from earlier years not offset correctly against the gain
- Connected-persons or market-value rules disputes on transfers between family members or related parties
Who Can Appeal?
Any individual or company that has made a chargeable disposal and disagrees with Revenue's resulting assessment can appeal. Valuation disputes in particular benefit from an independent valuation report submitted alongside the notice of appeal — this is the single strongest piece of evidence in a CGT valuation dispute.
What Must Your Notice of Appeal Include?
- Your full name and address (or company name and tax reference)
- The Revenue assessment reference number
- The tax year of the disposal
- The asset disposed of and the amount assessed
- Your grounds of appeal — the specific valuation, relief or cost basis you dispute, and why
- A statement that the appeal is within the 30-day time limit
- A request that the assessment be reduced, discharged or varied
How to Lodge Your Appeal
Online
Submit through taxappeals.ie, uploading your notice of appeal as a PDF.
By Post
Tax Appeals Commission
Fitzwilliam Court
Leeson Close
Dublin 2
D02 YW24
Use recorded delivery so you have proof of submission within the 30-day window.
There is no fee to lodge a CGT appeal with the Tax Appeals Commission.
Draft your CGT appeal in 60 seconds
TaxAppeal.ie generates a properly-structured notice of appeal citing section 949I of the Taxes Consolidation Act 1997, formatted for the Tax Appeals Commission. Free preview — €9.99 for the clean PDF.
Draft My Appeal — Free PreviewFrequently Asked Questions
Do I need a professional valuation to appeal a CGT valuation dispute?
It is not a legal requirement to lodge the appeal, but a written valuation from a qualified valuer significantly strengthens your grounds and is usually necessary to succeed once the matter is examined on its merits.
Can I appeal if I already paid the CGT under self-assessment and Revenue later amended it?
Yes — Revenue's amended assessment following a review is a fresh assessment with its own 30-day appeal window, regardless of what you self-assessed and paid originally.
What if the dispute is about whether PPR relief applies at all?
This is treated as a grounds-of-appeal question like any other — set out the facts of your occupation of the property clearly and in date order, since PPR relief disputes usually turn on the specific period of residence.