As the 2026 tax year progresses, staying on top of upcoming Revenue deadlines is essential for individuals, business owners, and companies alike.
Below is an overview of key Capital Acquisitions Tax (CAT), Capital Gains Tax (CGT), Income Tax, and Corporation Tax deadlines, along with practical points to keep in mind when filing.
| Tax Type | Standard Deadline | ROS Extended Deadline |
|---|---|---|
| Corporation Tax (31 Dec 2025 year end) | September 23rd 2026 | N/A |
| Income Tax (2025 Balance & 2026 Preliminary) | October 31st 2026 | November 18th 2026 |
| CAT (Valuation dates: September 1st 2025 to August 31st 2026) | October 31st 2026 | November 18th 2026 |
| CAT (Valuation dates: September 1st 2026 to December 31st 2026) | October 31st 2027 | ROS extension to be confirmed by Revenue |
| CGT (Asset disposals: January 1st to November 30th 2026) | December 15th 2026 | N/A |
| CGT (Asset disposals: December 1st to December 31st 2026) | January 31st 2027 | N/A |
Capital Acquisitions Tax (CAT)
The valuation date for CAT determines exactly when a return must be filed and when any potential liability must be paid.
- For a valuation date between 1 January and 31 August, the standard pay and file deadline is 31 October of that year.
- For a valuation date between 1 September and 31 December, the pay and file deadline is 31 October of the following year.
Where the IT38 return is filed online and payment is made via the Revenue Online Service (ROS), the deadline for gifts or inheritances with valuation dates in the year ended 31 August 2026 is extended to 18 November 2026. Both payment and filing must be completed via ROS to qualify.
Determining the valuation date can be straightforward for a gift (usually the date of the transfer), but more complex for an inheritance.
Common Inheritance Valuation Dates
- Most inheritances from an estate: The valuation date is usually around the date of grant of probate or when administration of the estate is completed.
- Specific assets where you take possession immediately (or already had possession): The valuation date can be as early as the date of death.
- Assets passing by survivorship (for example, joint tenancy), gifts in contemplation of death, or a failure to revoke a gift: The valuation date is the date of death.
Generally, an inheritance valuation date is the earliest of three dates:
- First, the date the executor is entitled to retain the asset for your benefit.
- Second, the date on which the asset is actually retained.
- Third, the date the executor gives the asset to you.
Do you need to file? A return is required even if no tax is owed if the value of the gift or inheritance exceeds 80 percent of the relevant tax free group threshold, or if you are claiming vital reliefs like Agricultural Relief or Business Relief.
Capital Gains Tax (CGT)
The critical trap with CGT is that payment is due long before the actual tax return is filed.
The 2026 payment timeline is split:
- For disposals between 1 January 2026 and 30 November 2026, payment is due by 15 December 2026.
- For disposals between 1 December 2026 and 31 December 2026, payment is due by 31 January 2027.
For companies, corporation tax on capital gains is usually due in line with standard corporation tax timelines. However, if a company disposes of development land giving rise to a CGT liability, the payment must follow the strict timeline outlined above.
Filing the Return: If you file a Form 11 Income Tax return, your 2026 CGT disposal details will be included in that return (filed in late 2027). For PAYE earners with minor non PAYE income, a Form 12 or Form CG1 can be utilized depending on your personal circumstances.
Income Tax
The standard pay and file deadline for the 2025 tax year is 31 October 2026. However, for taxpayers who both file their Form 11 return and pay online through ROS, the deadline is extended to 18 November 2026.
When filing your return, you must also calculate and pay your 2026 Preliminary Tax.
To avoid interest and penalties, your preliminary tax payment must equal or exceed the lower of:
- Either 90 percent of the final tax due for the 2026 tax year,
- or 100 percent of the final tax due for the 2025 tax year.
Corporation Tax
While specific accounting periods dictate compliance timelines, companies with a financial year end of 31 December 2025 must file their Form CT1 and pay any balancing tax by 23 September 2026.
Preliminary tax obligations must also be carefully managed:
- Large Companies with a 1 January to 31 December 2026 accounting period must pay their preliminary tax in two instalments. The first is due by 23 June 2026 and the second by 23 November 2026.
- Small Companies can pay in a single instalment by 23 November 2026.
Other Ongoing Compliance Requirements
While these dates mark the major milestones for the coming months, they operate alongside routine compliance cycles including bi monthly VAT returns (due on the 23rd of the month following the period), monthly payroll taxes, Stamp Duty, and Dividend Withholding Tax (DWT).
If you are uncertain about the correct treatment of a transaction or want to ensure absolute accuracy ahead of these deadlines, professional advice is highly recommended.
Need Advice?
At ECOVIS, our dedicated tax team advises individuals, business owners, and corporate clients on comprehensive tax compliance, structured filing obligations, and proactive tax planning.
If you would like assistance with an upcoming deadline or want to discuss your specific tax position, please get in touch with our team for a confidential discussion.
- Phone: +353 1 8230000
- Email: info@ecovis.ie
- Website: www.ecovisdca.ie
