RTB Rent Review Notice Checker
Which rent setting rule applies, when you may next review, and what makes the notice valid under the rules from 1 March 2026.
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Ireland · Rent Setting Evidence
The RTB Rent Register, and the three comparables rule
Since 1 March 2026 a landlord who resets rent to market value has to prove the figure with three real tenancies from the RTB Rent Register. This is what the register holds, how to build a set of comparables that stands up, and where the data is weaker than it looks.
Comparables needed: 3
Must have begun: in the last 3 months
Match on: size, type, character, BER
What is the RTB Rent Register?
The RTB Rent Register is a public database of rents actually being paid in registered tenancies in Ireland, built from RTB tenancy registrations and updated daily. It replaced the older quarterly Rent Index as the reference point for what a property should let for, and it is now the only evidence base the law recognises for proving a market rent.
It matters because of one specific obligation. From 1 March 2026, a landlord who is permitted to reset rent to market value must serve a notice stating that the new rent is not above market rent, and back that statement with three comparable tenancies from the register. Each has to be a property of similar floor area, number of bedrooms and bed spaces, type and character including Building Energy Rating, in a similar area, begun within the last three months, and each has to be cited by its Registered Tenancy number. Get this wrong and the rent setting is invalid, and the RTB can investigate and sanction.
Note the boundary: the register is for a market rent reset, which only some tenancies qualify for. An ordinary annual rent review is capped at the lower of CPI or 2% and needs no comparables at all.
What the register holds on each tenancy
The register was extended for the 2026 rules so that a like-for-like comparison is actually possible. The fields below are what you can search and what you can cite.
| Field | What it is used for |
|---|---|
| Rent | The rent recorded for the tenancy. This is the figure your comparison rests on. |
| Registered Tenancy number | The identifier you must quote in the notice for each of the three comparables. |
| Local electoral area | The geographic unit for "similar area". It is finer than a county and coarser than a street. |
| Dwelling type | House, apartment or other. A house is not a comparable for an apartment. |
| Bedrooms and bed spaces | Bed spaces matter for student accommodation, where the letting unit is a bed rather than a dwelling. |
| Floor area | Banded, not exact. This is the field that most often forces a wider search. |
| Building Energy Rating | Added specifically for the comparables test. A stale or missing BER now costs money at review time. |
| Tenancy start date | Determines whether a comparable is inside the three month window. |
The BER field is the one that catches landlords out
BER was added to the register because the 2026 rules make it part of the comparability test. That cuts both ways. If your own property has no current BER certificate, or holds an old rating that no longer reflects work you have done, you are comparing against a worse version of your property than the one you are letting, and the market rent you can evidence drops accordingly. Getting the BER re-assessed before a reset is often worth more than the assessment costs.
How to pull three comparables that hold up
The register is searchable on rtb.ie. The work is not finding three rows, it is finding three rows that a dispute adjudicator would accept.
Confirm you are allowed to reset at all
Comparables are only relevant to a market rent reset. If the tenancy began before 1 March 2026 and is continuing, you almost certainly cannot reset, and the cap is the lower of CPI or 2%. Resetting after a no-fault termination is prohibited outright. Establish the pathway first, because everything below is wasted effort otherwise.
Search your own local electoral area first
Start with the tightest geography and widen only if you cannot fill three. A comparable from an adjoining area is defensible; one from a different town is not, even if the property matches on every other field.
Match type, bedrooms and bed spaces exactly
These are the fields with no room for interpretation. A three bed house is not a comparable for a three bed apartment, and in student accommodation the bed space count is the unit of letting rather than the dwelling.
Get floor area and BER as close as you can
Floor area is banded, so aim for the same band. BER should be within a grade. Where you have to accept a gap, note it and be ready to explain why the comparable is still fair rather than hoping nobody checks.
Filter to tenancies begun in the last three months
This is a hard cut-off and the one most likely to break a set you have already assembled. A perfect match from five months ago does not count. In a thin local market this is what forces you to widen the geography rather than the age.
Record the Registered Tenancy number for each
The notice cites the number, not a description. Capture all three at the point of search, along with the date you searched, because the register moves daily and you may need to show what it said when you relied on it.
Serve the notice and copy the RTB the same day
The statement, the three comparables and an RTB Rent Calculator printout go to the tenant, and a copy goes to the RTB on the same day. A notice not copied to the RTB on the day it is served is invalid no matter how good the comparables are.
How accurate is the register?
This is the question landlords and tenants both ask, and it deserves a straight answer rather than a reassurance. The register is the best rent data Ireland has ever had, and it still has three known weaknesses worth understanding before you rely on it.
It reflects registrations, not the market
Only registered tenancies appear. Unregistered lettings, and any tenancy where the registered rent was never updated after a review, are invisible. In areas with weaker registration compliance the sample thins out quickly, which shows up as too few comparables inside the three month window.
It lags, by design
A tenancy appears once it is registered, not when it is agreed, and registration has its own deadline. In a fast moving market the three month window can therefore describe rents agreed rather earlier than three months ago. That matters most when the market is turning.
Banded fields hide real differences
Floor area is banded and character is a judgement. Two properties can match on every register field and still be worth materially different rents because one has parking, a garden, or a very different condition. The register proves a range, not a price.
The practical implication: treat three valid comparables as the floor of your evidence, not the whole of it. If your figure sits at the top of what the comparables support, keep a note of why the property justifies it. If it sits above them, the reset is not defensible and the notice should not be served.
RTB Rent Register questions
How do I search the RTB Rent Register?
The register is searchable free on rtb.ie. You filter by local electoral area, dwelling type, number of bedrooms and bed spaces, floor area band and Building Energy Rating, and each result shows the rent and the Registered Tenancy number. There is no account needed to search. The register updates daily from RTB tenancy registrations.
How many comparables does a rent setting notice need?
Three. Each must be a tenancy from the RTB Rent Register for a property of similar floor area, bedrooms and bed spaces, type and character including BER, in a similar area, that began within the last three months, and each must be identified by its Registered Tenancy number. They are used to prove the new rent is not above market rent.
What if I cannot find three comparable tenancies?
Widen the geography before you widen anything else, because the three month window is a hard rule and type and bedroom count are not negotiable. Move to an adjoining local electoral area with a similar rental market and document why it is comparable. If you still cannot assemble three, you cannot evidence a market rent reset, and the safe course is to apply the standard cap of the lower of CPI or 2% instead. Contact the RTB before serving anything unusual.
Do I need comparables for an ordinary rent review?
No. An annual rent review is capped at the lower of CPI inflation or 2% and needs no comparables. The three comparables requirement applies only where a landlord is resetting rent to market value, which is permitted in defined circumstances such as the start of a new tenancy that did not follow a no-fault termination, or the end of a six year tenancy of minimum duration.
Is the RTB Rent Register the same as the Rent Index?
No. The RTB Rent Index was a quarterly statistical report on average rents by area, useful for understanding trends. The Rent Register is a live record of individual registered tenancies with their rents, searchable property by property. Only the register can supply the named comparables a rent setting notice requires.
Can tenants use the register too?
Yes, and it is the most useful check a tenant has. If you receive a notice resetting the rent to market value, the three comparables it cites are verifiable: look up each Registered Tenancy number, confirm the properties really are similar in size, type, bedrooms and BER, and confirm each tenancy began within the last three months. A notice citing comparables that do not match, or that is not copied to the RTB the same day, is invalid and can be disputed.
Sources: RTB Rent Register and RTB guidance on setting and reviewing private rents from 1 March 2026, under the Residential Tenancies (Miscellaneous Provisions) Act 2026. This page is general information, not legal advice. Confirm your comparables and pathway with the RTB before serving a rent setting notice.
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Rentalize keeps the rent history, review dates, BER records and notice trail for every tenancy in one place, so a rent setting notice is assembled from records you already hold rather than rebuilt by hand each time.
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