Can I Appeal a Revenue Decision After 30 Days?

The standard deadline to appeal a Revenue assessment to the Tax Appeals Commission is 30 days from the date of the notice, under section 949I of the Taxes Consolidation Act 1997. If that window has already passed, you have not necessarily lost your right to appeal — but you need to act immediately, because a late appeal is not automatic.

How the Late Appeal Process Works

Under section 949O of the Taxes Consolidation Act 1997, the Tax Appeals Commission has discretion to accept a notice of appeal made after the 30-day deadline, but only where it is satisfied there was a reasonable cause for the delay and the application was made without unreasonable delay once that cause ceased.

This means a late appeal application has two separate things to establish:

1. A reasonable cause for missing the original 30-day deadline
2. That you acted promptly once you were able to appeal, rather than sitting on the matter

What Counts as "Reasonable Cause"?

There is no exhaustive legal list, but circumstances that have been accepted in practice include:

• Serious illness or hospitalisation during the appeal window
• The Revenue notice was not properly delivered or was sent to an outdated address
• A genuine and demonstrable error by an agent or adviser, promptly corrected once discovered
• Other exceptional circumstances outside your control that prevented you from appealing in time

Simply being unaware of the 30-day rule, being busy, or general oversight is unlikely on its own to be accepted as reasonable cause — the Commission expects taxpayers to know and act on the deadlines printed on Revenue's notices.

How to Apply for a Late Appeal

You submit your notice of appeal in the normal way — through taxappeals.ie or by post to Fitzwilliam Court, Leeson Close, Dublin 2, D02 YW24 — but you must additionally include a clear, separate written explanation covering:

1. Why the appeal is late
2. The specific reasonable cause you are relying on
3. Why you acted without unreasonable delay once that cause ended
4. Your full grounds of appeal against the underlying assessment, exactly as you would for an in-time appeal

What If My Late Appeal Application Is Refused?

If the Commission refuses to admit a late appeal, the original Revenue assessment stands as final and payable. This is why submitting a late appeal application at the earliest possible moment — with your strongest evidence of reasonable cause — matters so much; there is generally no second attempt.

Frequently Asked Questions

Is there a maximum time limit for a late appeal?

The legislation does not set a fixed outer deadline, but the longer the delay, the harder it becomes to satisfy the Commission that you acted without unreasonable delay — treat every extra week as working against you.

Do I still need full grounds of appeal, or just an explanation for being late?

Both. The late appeal explanation only gets your notice admitted — the Commission still decides the underlying tax dispute on its grounds, so include your full grounds of appeal exactly as you would in an in-time appeal.

Can I ask Revenue directly instead of the Tax Appeals Commission?

Revenue has separate internal review mechanisms for certain disputes, but a formal notice of assessment that you disagree with is appealed to the independent Tax Appeals Commission, not decided by Revenue itself.