Ireland: cumulative PAYE and the credits payroll never sees
Irish payroll gets an employee's tax right to the cent on what Revenue knows. PAYE is cumulative: on every pay day your employer works out the tax on all your pay since 1 January, against all the credits and rate band on your Tax Credit Certificate so far, and deducts the difference. So a PAYE employee rarely overpays by accident. An Irish refund nearly always comes from something you never told Revenue about.
The usual candidates are reliefs that only you can claim. The Rent Tax Credit is 20% of the rent you paid, up to €1,000 a year, or €2,000 for a jointly assessed couple, for 2024 to 2028. Health expenses such as GP and consultant fees, prescriptions and non-routine dental work are relieved at 20%. Tuition fees for a third-level course are relieved at 20% once the first €3,000 of the claim is set aside (€1,500 when every course is part-time). Many occupations have a flat rate expense allowance agreed with Revenue, and anyone who worked from home can claim remote working relief on 30% of their electricity, heating and broadband bills, apportioned to the days worked at home. The last two come off income, so they save tax at your highest rate.
Every one of these reduces income tax only. None touches USC or PRSI, and none can bring your income tax below zero, so relief beyond the tax you paid is lost. USC can be overpaid too: a full medical card holder, or anyone aged 70 or over, with income up to €60,000 pays USC at no more than 2%, and if payroll charged the standard rates the difference comes back in the same review.
To claim, sign in to myAccount, choose Review your tax for the previous 4 years, request a Statement of Liability and complete the Income Tax Return. Claims go back four years, so 2022 closes at the end of 2026. Credits for the current year can be added in Manage your tax instead, and the next pay returns what was overpaid.
Income tax deducted through the year: €8,800 at 20% plus €2,400 at 40%, less €4,000 of personal and employee credits = €7,200, which PAYE gets exactly right.
Rent of €1,250 a month is €15,000; 20% is €3,000, capped at €1,000. Health expenses of €600 give 20% = €120.
Income tax due: €7,200 − €120 − €1,000 = €6,080. Refund: €7,200 − €6,080 = €1,120. USC is unchanged, because neither relief reduces it.