Rent-a-Room calculator
What should you charge for the spare room?
Two questions, one answer. What a room like yours goes for where you live, and whether letting it keeps you inside the €14,000 you can earn tax free. Move the controls and both numbers move with you.
Tell us about the room
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€632a month, per room
Most rooms like it go for €582 to €683.
Over a year€7,589
Against the €14,000 limit
€0€14,000
Comfortably inside. You have €6,411 of room left before tax comes into it.
How we got there
- 1Whole property in Dublin€2,232RTB Rent Index, Q4 2025, new tenancies
- 2Split across 3 bedrooms€744One room's share of the rent
- 3You live there too€632Down 15%. A room in an occupied family home lets for less than a room in a house share, because the person taking it gets less of the place to themselves.
Step one is the RTB's figure. Every step after it is our own judgement, and we would rather say so than dress it up.
How the €14,000 works
Let a room in the home you live in and the first €14,000 you make from it in a year is free of income tax, USC and PRSI. No landlord tax return, no RTB registration, no tenancy. For most homeowners it is the most generous relief they will ever qualify for, and plenty of people never hear about it.
The catch is the shape of the limit. Most tax thresholds only tax the slice above the line. This one does not. Go a euro over €14,000 and the whole amount becomes taxable income, so the last €100 of rent can cost you thousands. Somebody charging €1,200 a month is over the limit before the year is out.
Everything the lodger hands you counts. Rent, obviously, but also money for the electricity, the heating, the broadband, the bins, meals, the washing. Add it all up before you decide you are safely under.
Who qualifies
- The property has to be your own home, lived in for the greater part of the year. A second property or a rental you own does not count.
- The letting has to be long term. Revenue draws the line at stays of more than 28 days in a row, so short lets are out.
- You can let more than one room. The €14,000 covers all of them together, which is the trap the calculator above is built to show you.
- You cannot claim it on a room let to your own employer, or to a child of yours paying rent.
Still tell Revenue
Tax free does not mean nothing to file. You still declare the income and claim the relief on your annual return. PAYE workers use a Form 12 through myAccount. Anyone self assessed uses a Form 11 through ROS. Miss it and the relief is not applied, even though you were under the limit all along.
Where these numbers come from
The starting figure is the RTB's standardised average rent for new tenancies in your county, covering October to December 2025 and published in May 2026. Nationally that sits at €1,755 a month, up 5% on the year.
That figure is for a whole property, so it is a market anchor rather than a room price. The calculator splits it across the bedrooms you tell it about, then adjusts for the things that make a room in an occupied home different from a room in a house share. Those adjustments are ours, not the RTB's, and you can open the working to see every one. We keep the two apart on purpose. A number wearing the RTB's name should be the RTB's number.
Treat the result as a starting point, not a valuation. A room five minutes from a campus in a town with nothing else going lets for more than the maths says. A room up three flights of stairs with a window over the bins lets for less.
Common questions
How much can I earn from renting a room before I pay tax?
€14,000 a year, across every room you let in the home you live in. Anything the lodger pays you for food, bills or laundry counts towards the same €14,000. Stay under it and the income is free of income tax, USC and PRSI.
What happens if I go over €14,000?
You lose the relief on the whole amount, not just the part above the limit. Earn €14,100 and all €14,100 is taxable. Earning slightly less can leave you better off, which is the one bit of this scheme worth doing the sums on.
Do I still have to tell Revenue if I stay under the limit?
Yes. The income is tax free but it is not invisible. PAYE workers declare it on a Form 12 through myAccount, and anyone self assessed uses a Form 11 through ROS. Claim the relief on the same return.
Does the room have to be in my main home?
Yes. Revenue expects the property to be your sole residence for the greater part of the year, and the place people would normally contact you. A second home or an investment property does not qualify.
Does a short stay count?
No. The letting has to be long term, which Revenue treats as stays of more than 28 days in a row. Short lets and guests passing through are outside the scheme.
Where do the rent figures come from?
The starting number is the RTB's standardised average rent for new tenancies, October to December 2025. That is a whole property figure, so the calculator splits it across the bedrooms in the house and then adjusts for the things that make a room in an occupied home different. Those adjustments are our own judgement and the page shows every one of them.
Do I need to register with the RTB?
No. Somebody renting a room in the home you live in is a licensee, not a tenant, so the Residential Tenancies Act does not apply and there is nothing to register. Put the arrangement in writing anyway, because neither side has the fallback of tenancy law.
General information, not tax advice. Revenue's own guidance is the authority here, and an accountant is worth an hour of anybody's money the first year they let a room.
Sources: RTB Rent Index, Citizens Information on renting a room, and Revenue on rent-a-room relief.
Next: the full €14,000 explainer, a lodger agreement you can fill in, or how to write the listing.