How to Appeal a Corporation Tax Assessment in Ireland (2026 Guide)
Small and medium companies who receive a corporation tax assessment they disagree with — an estimate raised after a late CT1 return, disallowed trading deductions, or a dispute over capital allowances — have the right to appeal 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 — counted from the date printed on the notice, not the date received.
Common Reasons a Company Appeals a CT Assessment
- An estimated assessment — Revenue raised a CT liability without the company's CT1 return
- Disallowed trading expenses — legitimate deductions rejected as non-trading or capital in nature
- Capital allowances disputes — disagreement over allowances claimed on plant, machinery or property
- Group relief or loss relief refused — reliefs claimed between group companies not accepted
- Close company surcharge disputes — surcharge on undistributed investment or professional income wrongly applied
Who Can Appeal?
A director, company secretary, or an agent with authority to act for the company can lodge the notice of appeal. You do not need a solicitor to appeal, though for disputes involving capital allowances, transfer pricing, or group relief structuring, involving your accountant in drafting the grounds is strongly advisable given the technical detail involved.
What Must Your Notice of Appeal Include?
- The company name and tax reference number
- The Revenue assessment reference number
- The accounting period in dispute
- The amount assessed or disputed
- Your grounds of appeal, each stated separately and referencing the relevant deduction, allowance or relief
- A statement that the appeal is within the 30-day time limit
- A request that the assessment be reduced, discharged or varied
If the assessment is an estimate raised because a CT1 return was late, submitting the completed return with your notice of appeal is usually the fastest path to resolution.
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 corporation tax appeal with the Tax Appeals Commission.
Draft your corporation tax 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
Can a company director appeal without a solicitor?
Yes. A director or authorised agent can lodge the notice of appeal directly. Legal representation becomes more useful only if the dispute proceeds to a formal hearing on a technical point.
Does appealing pause the company's payment obligation?
No — lodging an appeal does not suspend the underlying payment obligation or stop interest accruing on any amount ultimately due, so it is worth discussing payment-on-account options with Revenue in parallel with the appeal where cash flow is a concern.
Can I appeal after the CT1 has already been filed correctly but Revenue queries it?
Yes — if Revenue raises an amended assessment following a review or audit of an already-filed CT1, that amended assessment is separately appealable within 30 days of its own date.