Ireland’s 2% RPZ Cap Explained: What Landlords Must Do Before Their Next Rent Review

On 1 March 2026, the rules of the Irish rental market changed for every landlord, in every county. Rent Pressure Zones, which until then covered roughly 83% of the population, were extended to the entire State as part of the new rental laws that took effect on 1 March 2026. The annual cap on rent increases for existing tenancies was reset to the lower of 2% or the Harmonised Index of Consumer Prices.

If you are a landlord in Ireland, two things are now true. First, almost every rent review you carry out for the next several years will be capped. Second, getting that calculation wrong, even by a few euro, exposes you to a Residential Tenancies Board determination that can wipe out years of margin.

This guide walks through what changed, how to calculate a compliant new rent, the paperwork the RTB will look for, and where most landlords slip up.

What actually changed on 1 March 2026

Three things changed at once, and it is easy to confuse them:

• RPZ coverage. Every Local Electoral Area in Ireland is now a Rent Pressure Zone. There is no longer a non-RPZ option for existing tenancies. The full picture, including the supply context, is set out in our 2026 Irish rental market analysis.
• The cap formula. For tenancies signed before 1 March 2026, the maximum permissible increase at review is the lower of 2% per annum or the HICP rate published by the CSO for the relevant period.
• Minimum tenancy term. New tenancies created on or after 1 March 2026 carry a minimum six-year term. Landlords cannot serve a no-fault termination during that period.

These three changes interact. A landlord who signs a brand new tenancy in 2026 is locked into a six-year arrangement, and every rent review inside that arrangement is governed by the 2% / HICP formula. The era of resetting rent to market between tenancies, for the same property, is effectively over for the duration of an existing landlord-tenant relationship.

How to calculate a compliant rent review

The formula the RTB will apply if a tenant disputes your review is straightforward, but every step matters.

1. Confirm you are eligible to review. Rent reviews can only happen once every twelve months. The first review of a new tenancy can occur no earlier than the first anniversary of the tenancy commencement date.
2. Establish the current rent. Use the rent stated on the most recent valid Notice of Rent Review or, if none exists, the rent in the original tenancy agreement.
3. Look up the HICP rate. The CSO publishes HICP monthly. You take the rate for the twelve-month period ending in the month before you serve the notice.
4. Compare 2% against the HICP rate. The permissible increase is whichever is lower. In a low-inflation environment, HICP wins. In a high-inflation environment, 2% wins.
5. Apply the percentage. Multiply the current rent by the permissible percentage. Round down, not up. The RTB does not penalise you for being a euro under, but it will penalise you for being a euro over.

Worked example. The current rent is EUR 1,800. HICP for the relevant period is 1.6%. The 2% cap is higher than 1.6%, so the permissible increase is 1.6%. New rent: EUR 1,800 x 1.016 = EUR 1,828.80, which you should round to EUR 1,828.

If your tenancy is in the social housing system rather than the private market, the calculation works differently. Local Authority and AHB tenants are charged differential rent, not market rent, and the 2% cap does not apply. Use our Differential Rent Calculator for that side of the sector. For Housing Assistance Payment tenancies, the HAP Calculator handles the tenant contribution.

The Notice of Rent Review

The calculation is half the job. The other half is the formal Notice of Rent Review served on the tenant. The RTB has prescribed content requirements and a minimum notice period of 90 days before the new rent can take effect.

A compliant notice must include:

• The current rent
• The proposed new rent
• The date the new rent will take effect (at least 90 days after service)
• The HICP rate used in the calculation, with the period it covers
• The 2% cap calculation as a comparison
• A statement that the property is in a Rent Pressure Zone (now true for the entire State)
• The tenant’s right to refer the notice to the RTB within 90 days

Notices that omit any of these elements are routinely set aside by RTB adjudicators. The single most common reason landlords lose rent review disputes is not the maths. It is the paperwork.

What it costs to get this wrong

The RTB has the power to declare an invalid Notice of Rent Review unenforceable, in which case the rent reverts to the previous level for the duration of the tenancy until a valid notice is served and twelve months pass. On a EUR 1,800 rent, a single mishandled review can cost a landlord between EUR 350 and EUR 700 over a year, plus the time and stress of the dispute itself.

For larger portfolios the maths is brutal. A property management company handling 200 units that mishandles 10% of its annual reviews is looking at a five-figure recurring loss, every year, and a compliance footprint that will be flagged the next time a fund or bank does diligence on the portfolio. We unpack the wider hidden cost of stitched-together compliance tooling in this analysis for Irish PMCs.

Where most landlords slip up

1. Using the wrong HICP period. The relevant period is the twelve months ending the month before notice is served, not the calendar year and not the month of service.
2. Forgetting the twelve-month rule. If your last review took effect on 1 June 2025, your next review cannot take effect before 1 June 2026, regardless of when you serve the notice.
3. Issuing notice by text or email only. The RTB requires written notice in a form the tenant can retain. Email is acceptable if the tenant has agreed to that channel in the tenancy agreement, but a text message alone is not.
4. Rounding up. EUR 1,800 x 1.016 is EUR 1,828.80. Charging EUR 1,829 is over the cap. Charge EUR 1,828.
5. Forgetting that the cap applies between tenancies too. If a tenant moves out and a new one moves in, the rent for the next tenant is constrained by the same RPZ formula, not by market rates. There are narrow exceptions for substantial refurbishment, but the threshold is high and the RTB tests it strictly.

What to do this week

If you have any rent reviews scheduled in the next six months, do three things now.

First, pull your tenancy file and confirm the date of the last review for each property. Diary the earliest date you can serve a fresh notice (the previous review date plus twelve months minus 90 days).

Second, look up the latest HICP rate on the CSO website. If it is below 2%, plan around the HICP figure. If it is above, plan around 2%.

Third, draft your Notice of Rent Review using the RTB’s prescribed template, not a custom one. The template is updated as legislation changes, and using it removes the most common procedural challenges before they happen.

How Rentalize handles this for you

Rentalize Pay and Rentalize Core both calculate the permissible rent increase automatically against the live HICP feed and generate a compliant Notice of Rent Review with one click. The system flags reviews that fall outside the twelve-month window, applies the lower of 2% or HICP without the landlord needing to look anything up, and stores a dated audit trail of every notice served.

For landlords managing one to ten properties, Rentalize 360 does the same thing on a phone. For Local Authorities, AHBs and large PRS portfolios, Rentalize Core ties the RPZ workflow into rent collection, arrears tracking and RTB registration, so the same compliance posture covers the whole portfolio. Tenant selection ahead of any new six-year tenancy is handled by Rentalize Select.

The 2% cap is not going away. The volume of rent reviews you will run between now and the end of the decade is only going up. Getting the process right once, in software, is cheaper than getting it wrong twice, in front of an RTB adjudicator.

If you would like to see the rent review workflow inside Rentalize, you can book a 20-minute walkthrough. We will use one of your own properties as the worked example.

Frequently asked questions

Does the 2% RPZ cap apply to every property in Ireland?

Yes. From 1 March 2026, every Local Electoral Area in Ireland is a Rent Pressure Zone. Existing private tenancies are subject to the lower of 2% per year or HICP at every rent review.

What if HICP is higher than 2%?

The cap is whichever is lower. If HICP is 3.4%, you can still only raise the rent by 2%. If HICP is 1.1%, you can only raise it by 1.1%.

Can I reset the rent to market when a tenant leaves?

No, not under the standard rules. The RPZ formula follows the property, not the tenancy, with narrow exceptions for substantial refurbishment that the RTB tests strictly.

Does the RPZ cap apply to social housing?

No. Local Authority and AHB tenancies use differential rent, calculated from household income. See our Differential Rent Calculator and Cost Rental guide for the social and affordable side of the sector.

How long must a rent review notice run before the new rent takes effect?

A minimum of 90 days from the date of valid service. Shorter notices are routinely set aside on referral to the RTB.

What is the penalty for getting the calculation wrong?

The RTB can declare the notice invalid. The rent reverts to the previous level until a fresh, valid notice is served and a further twelve months pass.