Rent-a-Room Relief Calculator

A relief with a hard edge

Rent-a-Room relief is one of the most generous exemptions in the Irish tax code, and also one of the most unforgiving if you misjudge it. Rent out a room, or rooms, in the home you live in, and as long as the gross income for the year stays at €14,000 or below, the whole lot is exempt from income tax, USC, and PRSI. You keep every cent. This calculator checks where you stand against that ceiling and shows the tax that lands if you cross it.

The defining feature is that it is a cliff-edge relief, not a deduction or a tapered allowance. You do not get the first €14,000 tax-free and pay tax only on the surplus. Go even one euro over the limit and the entire amount becomes taxable from the first euro, at your marginal income tax rate. That is the trap the tool is built to expose.

The cliff at €14,000, illustrated

The arithmetic of the cliff is brutal and worth seeing plainly. Suppose you are a standard-rate taxpayer. Charge €14,000 for the year and you keep all €14,000, with no tax. Charge €14,500, just €500 more, and you lose the relief entirely. The whole €14,500 is now taxable. At 20 percent that is €2,900 of tax, leaving you €11,600. By earning €500 more in rent you have ended up €2,400 worse off. The table below sets the two scenarios side by side.

The charges people forget to count

Owner-occupiers thinking of letting a spare room, parents with a student digs arrangement, and anyone already renting a room who needs to check they are safely under the line will find this useful. The most common and costly mistake is forgetting what counts toward the €14,000. It is gross income, and it includes more than the bare rent. If your tenant pays you for food, utilities, laundry, or other ancillary services, those payments are added to the rent for the purposes of the limit. People breach the cliff by accident this way, having only watched the rent figure. Add everything up.

If you are anywhere near the line, the advice is blunt. It is usually better to deliberately keep the total at or just under €14,000 than to nudge slightly over and trigger tax on the whole sum. If you are likely to exceed it, you can still elect out of the relief and instead be taxed as a normal landlord on the profit after expenses, which on a higher rent can work out better. The room must be in your own home and part of the residence, so a fully self-contained unit can fall outside the relief.

It also helps to know how the €14,000 limit behaves when more than one person owns the home or lets a room. The limit is per residence, not per person, so a couple who jointly own their home and let a room share a single €14,000 ceiling rather than getting one each. If two co-owners let rooms in the same property, the combined gross income is what counts against the limit. Tenancy length is flexible: the relief covers long-term lodgers, students during term, and longer-stay guests alike, as long as it is genuine residential accommodation in your home rather than short-term holiday letting, which is treated as a trade and falls outside this relief entirely. That distinction trips up people who switch a room between a long-term lodger and short holiday stays.

Does the relief affect my Help to Buy or mortgage interest position?

Claiming Rent-a-Room relief does not jeopardise your status as an owner-occupier, so it does not clash with having bought as a first-time buyer. It is specifically designed for people letting a room in the home they live in. It does not turn your home into an investment property for Capital Gains Tax either, so Principal Private Residence relief on the house is unaffected.

Do I still have to tell Revenue if I am under the limit?

Yes. Even when the income is fully exempt, you are required to declare it on your annual tax return and claim the relief. It is not automatic. If you simply leave it off the return, the exemption can be refused, so report the figure and tick the relief each year.