Ireland Tax Calendar 2026: Key Dates & Deadlines
Missing an Irish tax deadline usually doesn't mean anything dramatic happens overnight, but it can mean interest charges, surcharges, or a refund that takes months longer than it should. Here's what's actually on the calendar for 2026.
One thing to establish first, because it saves most PAYE employees a lot of unnecessary anxiety: most of these dates don't apply to you. The 31 October deadline is a self-assessment deadline. If you're a straightforward employee claiming credits and reliefs, you're on a four-year clock instead, and there's no date in October you can miss.
| Date | What it is | Who it applies to |
|---|---|---|
| 1 Oct 2026 | Employee PRSI rises to 4.35% | All employees |
| 31 Oct 2026 | Form 11 return + balance for 2025, preliminary tax for 2026 | Self-assessed |
| 31 Oct 2026 | CGT return for 2025 disposals (CG1 or Form 11) | Anyone who disposed of an asset in 2025 |
| 31 Oct 2026 | CAT pay & file, valuation dates 1 Jan – 31 Aug 2026 | Gift and inheritance recipients |
| 18 Nov 2026 | Extended ROS deadline for the above | ROS filers who both file and pay online |
| 15 Dec 2026 | CGT payment for disposals 1 Jan – 30 Nov 2026 | Anyone with a 2026 gain |
| 31 Dec 2026 | 2022 tax year closes for refund claims | Everyone |
| 31 Jan 2027 | CGT payment for December 2026 disposals | Anyone with a December gain |
31 October 2026 — Self-assessed return & payment
If you file a Form 11 — self-employed, landlords, company directors, people with significant investment or foreign income — this is your main date. Three things are due together:
- Your 2025 return.
- The balance of 2025 tax owed.
- Preliminary tax for 2026.
Preliminary tax is the part people underestimate. You can base it on whichever of these suits your position: 100% of your 2025 liability (simplest and safest), 90% of your estimated 2026 liability (useful if your income has dropped), or 105% of your 2024 liability (direct debit payers only). Undershoot and Revenue charges interest.
The ROS extension for 2026 is 18 November. It isn't automatic — you have to both file and pay through ROS to get it. Filing online and paying by transfer doesn't qualify.
Miss the deadline and there's a surcharge on the tax due: 5% if you're up to two months late, 10% beyond that, with interest accruing daily on any unpaid balance.
31 October 2026 — Form 12 for PAYE reliefs
This one isn't actually a deadline for you, and that's worth saying plainly.
If you're a standard PAYE employee claiming credits or reliefs that aren't applied at source — Rent Tax Credit, medical expenses, remote working relief, flat rate expenses — you do not have to file by 31 October. You have four years from the end of the tax year concerned, and you can file any day of any of them.
You'll still see "Form 12" referenced in older guidance. In myAccount today you're completing a PAYE Income Tax Return, which is the same thing. The paper Form 12 and the simplified Form 12S still exist for people who can't use online services, but very few people need them.
The 31 October date only becomes yours if you have non-PAYE income significant enough to make you a chargeable person — rental income, foreign income, meaningful investment income. If you're not sure which side of that line you're on, resolve it before assuming, because being wrong in that direction is the expensive one. Revenue sets out the PAYE process on its Income Tax Return page, and we walk through it in claiming your PAYE tax back for the first time.
15 December 2026 — CGT payment (initial period)
If you disposed of an asset — shares, crypto, property — between 1 January and 30 November 2026, any CGT due must be paid by this date.
Note what this date is not. It's a payment deadline, not a filing one. The return declaring those same 2026 disposals isn't due until 31 October 2027, and you must file it even if losses or the €1,270 annual exemption mean no tax is payable.
Paying in December and forgetting to file the following October is one of the most common ways people end up with a surcharge on a liability they'd already settled. The mechanics are covered in crypto tax in Ireland, and they apply identically to shares and property.
31 January 2027 — CGT payment (later period)
Gains made in December 2026 have their own, later payment deadline.
This catches people out because it's counter-intuitive: a disposal on 30 November is payable within about two weeks, while a disposal on 1 December gets fourteen months. People assume all gains in a year follow the same rule, and December sellers are the ones who get it wrong in the expensive direction — by assuming they've missed a deadline that hadn't arrived, or by paying into the wrong period.
CAT deadlines
Gifts and inheritances run on their own calendar, and it's the one most likely to produce an unexpected surcharge. Which deadline applies depends on your valuation date:
| Valuation date | Pay and file by |
|---|---|
| 1 January – 31 August 2026 | 31 October 2026 |
| 1 September – 31 December 2026 | 31 October 2027 |
If you file and pay through ROS, valuation dates in the year ended 31 August 2026 extend to 18 November 2026.
You must file a Form IT38 if what you've received exceeds 80% of your relevant group threshold, counting everything received in that group since 5 December 1991 — even where no tax is due. The full picture is in inheritance tax in Ireland.
The rolling 4-year refund window
Refund claims don't have a single calendar date. You have a rolling four-year window from the end of each tax year, so as of 2026 you can still claim for 2022, 2023, 2024 and 2025.
But there is one hard date in this, and it's the most important one on this page for most readers:
31 December 2026 — the 2022 tax year closes permanently.
After that, whatever you were owed for 2022 is gone. Not deferred, not recoverable on appeal — gone. If you were renting in 2022, had medical expenses in 2022, worked from home in 2022, or started a job partway through 2022, that's the year with a clock on it.
If you'd rather have all four open years reviewed properly before the oldest one closes, that's what our Tax Return service does.
Mid-year: the PRSI change
2026 has one quirk worth flagging: employee PRSI (Class A) increases from 4.2% to 4.35% from 1 October 2026, under the multi-year PRSI schedule. Employer rates rise by the same 0.15 percentage points.
For most employees it's not a deadline to act on — just a small dip in net pay from October if you're budgeting the second half of the year.
For anyone filing a Form 11, though, it's a calculation detail rather than a footnote: 2026 isn't a single-rate year, so your annual PRSI is a blend of nine months at 4.2% and three at 4.35%. If you're estimating your own liability, don't apply one rate across the whole year.
Questions we get asked
How do I know if I'm self-assessed?
Broadly, if your only income is a salary taxed through PAYE, you're not. You become a chargeable person when you have non-PAYE income above the relevant limits — rental profit, foreign income, meaningful investment income, or income from a trade. If you're a proprietary director, you're in the self-assessment system regardless. If it's genuinely unclear, it's worth confirming rather than defaulting to the assumption that suits you.
I missed 31 October. What happens now?
File as soon as you can — the surcharge is 5% of the tax due if you're within two months of the deadline and 10% after that, so the gap between "late" and "very late" is real money. Interest runs separately on unpaid tax. Doing nothing is always the more expensive option.
Does the ROS extension apply automatically?
No. You have to both file the return and make the payment through ROS. Filing online and paying by bank transfer separately doesn't qualify, and Revenue confirms the exact date each year.
Do these deadlines still apply if I've left Ireland?
Yes, for any year in which you had an Irish tax obligation. myAccount and ROS both work from abroad. The practical constraint is usually a closed Irish bank account rather than the deadline itself — see leaving Ireland and the refund you might be owed.
Is there a deadline for claiming the Rent Tax Credit?
Only the four-year one. For 2022, that's 31 December 2026. There's nothing you have to do in October.