As a BER assessor who has visited thousands of rental properties across Dublin, Wicklow, and beyond, I have seen first-hand how often landlords overpay tax simply because they miss allowable deductions. Here are the seven most common mistakes.
Without RTB registration, you cannot claim mortgage interest as a deduction. For a landlord paying EUR 1,200 per month in mortgage interest, that is a potential deduction of EUR 14,400 per year lost entirely. The RTB fee is EUR 40 per tenancy per year.
There is a critical distinction between repairs (deductible) and improvements (capital expenditure, not deductible as a revenue expense). Replacing a broken boiler with one of similar specification is a repair. Installing an entirely new heating system as part of a renovation is an improvement. Keep records that clearly describe what was done and why.
You can claim 12.5% per year over 8 years on the cost of furniture, fittings, and appliances you provide. A EUR 3,000 kitchen fit-out generates EUR 375 per year in deductions for 8 years. Many landlords forget to claim this.
If your property was vacant for 12 months or more before being let, you can claim up to EUR 5,000 per property in pre-letting expenses. This covers repairs, cleaning, and advertising to get the property ready for tenants.
The Residential Premises Rental Income Relief is EUR 1,000 for 2026. It is a credit against your rental income tax, but you must keep the property in the rental market for 4 years or the relief is clawed back. Many landlords are unaware it exists.
If your rental income tax liability is significant, you must pay preliminary tax by 31 October (or mid-November for ROS filers). Late payment attracts interest at 0.0219% per day. Use the 100% prior year method for safety.
Revenue can audit your rental accounts going back 4 years (6 if careless). Without receipts, deductions will be disallowed. Keep everything: insurance certificates, repair invoices, management fee statements, letting agent receipts, and bank statements showing mortgage payments.
Our Rental Income Tax Report calculates every deduction, per property. EUR 49.
Get Your Report - EUR 49Disclaimer: This information reflects the 2026 tax year. Tax rules change annually following the Budget. Check Revenue.ie for the latest rates and thresholds. This guide is for informational purposes only and does not constitute tax advice.