Ireland Self-Employed Tax 2025 — Form 11 & Preliminary Tax
Two payments due on the same day
Self-assessed taxpayers file Form 11 and pay tax under Ireland's "pay and file" system, which asks for two things at once, on the same deadline: the balance of tax due for the year just ended, and preliminary tax for the current year — an advance payment against a liability that is not yet finalised, because the year is still running.
How much preliminary tax you must pay
Preliminary tax must be at least the lowest of:
- 90% of the current year's actual tax liability
- 100% of the prior year's tax liability
- 105% of the liability from the year before that — but only if you pay by direct debit, and only if that pre-preceding year's liability was not nil
In practice, most self-employed people use option 2 — 100% of last year's bill — because it is knowable in advance, whereas 90% of the current year requires forecasting a number you cannot be certain of until the year closes. Someone in their first year of self-assessment typically owes no preliminary tax at all, since the prior year's liability (option 2) is nil.
The deadline — and why online filers get longer
The standard pay and file deadline is 31 October, covering both the balance for the prior year and preliminary tax for the current year. Filers who both file and pay through ROS (Revenue Online Service) get a later date each year — commonly a few weeks into November — but the extension only applies if both the filing and the payment are done through ROS; doing one on paper and one online does not qualify.
What happens if you're late
Filed up to two months late: a surcharge of 5% of the tax due, capped at €12,695. Filed more than two months late: a surcharge of 10% of the tax due, capped at €63,485. The surcharge is calculated on the tax due for the year the return relates to, so a large liability can produce a large surcharge even after the cap is applied to bring it back down.
Worked example
A self-employed consultant had a tax liability of €28,000 for 2025 (paid in full by 31 October 2026, alongside their return) and forecasts a similar €28,000 liability for 2026.
- Option 2 (100% of prior year): preliminary tax due for 2026 = 100% × €28,000 = €28,000
- Option 1 (90% of current year), if forecast is reliable: 90% × €28,000 = €25,200
Using option 2 is simpler and safer here: if the consultant's actual 2026 income turns out higher than forecast, having paid 100% of the 2025 figure still satisfies the preliminary tax requirement, whereas an under-estimated 90%-of-current-year forecast would fall short and trigger interest on the shortfall.
If the same consultant instead files three months late, having a €28,000 balance still outstanding at that point, the surcharge is 10% of €28,000 = €2,800 — well under the €63,485 cap, so the full 10% applies without any reduction.
FAQ
Q: Do I need to register for self-assessment before I can file a Form 11? A: Yes — you register for income tax as a self-employed person (or for a new source of non-PAYE income) with Revenue before your first Form 11 is due.
Q: What if I overpay my preliminary tax? A: The overpayment is offset against your final liability once the actual figure for the year is known, and any remaining excess is refunded.
Q: Does the surcharge apply if I file on time but pay late? A: The surcharge under this rule attaches to late filing of the return itself; paying late separately attracts interest on the unpaid tax, calculated differently from the filing surcharge.
Sources
Figures verified against Revenue guidance as of 30 July 2026:
- Revenue — "What is preliminary tax?" (90%/100%/105% rules, direct-debit condition on the 105% option, nil-liability first-year exception)
- Revenue — "Pay and file system – how does it work?" (31 October standard deadline, later ROS deadline for online filers who both file and pay online)
- Revenue — "What charges are there for late filing?" / Tax and Duty Manual Part 47-06-01 (5% surcharge capped at €12,695 for returns up to two months late; 10% surcharge capped at €63,485 beyond two months)