Ireland taxes residents on worldwide income (historically subject to a remittance-basis option for non-domiciled residents on foreign investment income and gains, subject to conditions) and non-residents on Ireland-source income only. Ireland operates a self-assessment system, adopted in 1988 per IMF research: taxpayers calculate and file their own return via the Pay and File system, with Revenue conducting post-filing compliance checks rather than issuing a prior assessment.
The Irish tax year is the calendar year. The standard Pay and File deadline for individuals is 31 October following the end of the tax year; taxpayers who both file and pay via the Revenue Online Service (ROS) typically receive an extended deadline into mid-November, confirmed annually by Irish Revenue.
Ireland's headline corporate income tax (CIT) rate is 12.5% trading; 25% non-trading.
The headline personal income tax (PIT) rate is 40%.
The standard VAT/GST (or equivalent consumption tax) rate is 23%.
An individual is Irish tax resident for a tax year (which runs the calendar year) if present in Ireland 183 days or more that year, or 280 days or more combined across that year and the preceding year (with at least 30 days in each) - any part of a day counts as a full day present. After three consecutive years of tax residence, an individual becomes "ordinarily resident," a status that persists for three years after residence ends and keeps worldwide income within the Irish tax net even after departure. Residents (and ordinarily-resident/domiciled individuals) are taxed on worldwide income; others are taxed only on Irish-source income.
A non-Irish entity has an Irish permanent establishment through a fixed place of business or a dependent agent habitually concluding contracts in Ireland on the entity's behalf, following the OECD Model Treaty definition as applied under Irish domestic law and any applicable tax treaty.
Ireland's CFC regime (implementing EU ATAD) applies where an Irish company holds, alone or with associated enterprises, a direct or indirect participation of more than 50% (by voting rights, capital, or profit entitlement) in a foreign company. A charge arises on the Irish parent for the CFC's non-distributed income attributable to "non-genuine arrangements" put in place for the essential purpose of obtaining a tax advantage - broadly, where the CFC would not hold the relevant assets or bear the relevant risks if it were not controlled by the Irish company, and the significant decision-making functions relevant to those assets and risks are actually carried out in Ireland.
Ireland has no traditional debt-to-equity thin capitalization rule. Since accounting periods beginning on or after January 1, 2022, the ATAD-based Interest Limitation Rule (ILR) caps deductible net interest at 30% of tax-EBITDA, with several exclusions: a EUR 3 million de minimis, a standalone-entity exemption, a grandfather exclusion for legacy debt in place before June 17, 2016 and unaltered since, and a long-term infrastructure project exclusion. Companies may elect to apply the ILR on a single-entity or local-group basis. Separately, Section 247 TCA can restrict interest deductions on related-party acquisition financing, and payments to certain non-EU 75%-related affiliates can be recharacterized as a distribution and disallowed.
Ireland does not use an elective check-the-box classification system, though Irish entity forms (particularly the Irish Unlimited Company and certain partnership structures) have been used in international hybrid-entity planning given favorable treatment in some counterparty jurisdictions. Ireland has implemented ATAD2-aligned anti-hybrid rules denying deductions for payments producing a hybrid mismatch outcome.
No foreign bank account or foreign financial asset reporting regime exists in Ireland requiring residents to separately disclose foreign accounts; foreign income and gains are reported through the standard annual tax return.
Ireland does not provide a general participation exemption for dividends received by Irish companies from foreign subsidiaries in the way most EU peers do; instead, Ireland primarily relies on its foreign tax credit system (see Foreign Tax Credit below) to relieve double taxation on foreign dividends, though Ireland does provide a capital gains participation exemption for disposals of shares in qualifying trading subsidiaries resident in the EU or a tax treaty country, generally requiring at least 5% ownership held for a continuous 12-month period within the prior 24 months.
Ireland has a real foreign tax credit regime available to both individuals and companies for foreign tax paid on foreign-source income, generally operating under an applicable tax treaty or unilateral relief provisions, capped at the Irish tax otherwise due on that income.
Ireland has signed comprehensive double tax treaties with 78 countries, of which 75 are currently in effect (per Chambers and Partners, 2026) - agreements with Ghana and Kenya remained signed but not yet in force as of the most recent verification. Ireland ratified the OECD's Multilateral Instrument (MLI) in the Finance Bill 2018. Ireland's tax treaty policy, set out in a June 2022 statement, generally follows the OECD Model Tax Convention.