Chapter 3 of 10 · Rates, lenders and switching · 4 of 10
Green mortgages in Ireland: the BER rules and the rates
Checked 21 Oct 2026the Central Bank's mortgage measures, Revenue's rules and the scheme operators' published terms.
Which homes qualify for a green mortgage (usually BER A1 to B3), the discount each lender gives, and green top-ups for retrofits.
Check before you hire: a ber assessor should be on the register kept by SEAI. SEAI: register of BER assessors
Written in plain English for the person buying, selling or switching. This guide covers the Republic of Ireland only.
A green mortgage is an ordinary mortgage with a lower rate for a home that uses less energy. The lender decides that from the home's Building Energy Rating, or BER. This guide explains which homes qualify, how big the discount tends to be, and how to get a BER if you need one.
What a BER is
A BER (a Building Energy Rating) is a label for a home's energy use, from A1 (the least energy) to G (the most). A1 is the top rating and G is the bottom. The scale runs A1, A2, A3, B1, B2, B3, C1, C2, C3, D1, D2, E1, E2, F, G. See the glossary for other terms.
The law requires a BER before a home is advertised for sale or rent, and when a new home is finished. A certificate lasts 10 years. Only a BER assessor (on SEAI's register) can issue one. SEAI is the Sustainable Energy Authority of Ireland, the State body that runs the scheme. See what a BER assessor does.
Which homes qualify
Most green mortgage rates require a BER of B3 or better. That means one of six ratings: A1, A2, A3, B1, B2 or B3. Each lender sets its own threshold, and a few differ. Our green rates page shows the rating each lender asks for beside its rate.
In practice:
- A new build almost always qualifies. Homes built to current building regulations are rated A.
- A second-hand home built in the last fifteen years or so often qualifies.
- An older home usually does not, unless it has had insulation, new windows and a new heating system.
- A home you are about to retrofit does not qualify until the work is done and a new BER is issued.
The lender needs the certificate, not the advertisement. Ask the seller or the builder for the BER number so you can check it on SEAI's register.
How big the discount is
The discount is the gap between a lender's standard fixed rate and its green fixed rate for the same period and the same loan-to-value. In the indicative figures on our rates page in October 2026, that gap is about 0.2 to 0.25 of a percentage point. Those figures are placeholders until the weekly check replaces them, so look at the page for today's rates.
For context, the Central Bank's average new fixed rate in August 2026 was 3.49%.
A worked example
Say you borrow €300,000 over 30 years. The lender's standard 4-year fixed rate is 3.25% and its green rate is 3.05%.
| Standard rate 3.25% | Green rate 3.05% | |
|---|---|---|
| Monthly payment | €1,306 | €1,273 |
| Saving a month | About €33 | |
| Saving over the 4-year fixed period | About €1,560 |
A green rate does not change what you can borrow. The Central Bank limits and the lender's own tests are the same. Our repayment calculator shows your own figure at any two rates.
Getting a BER
If you are buying, the seller pays for the BER. It must exist before the home is advertised, so ask for it at the first viewing. A new build gets its BER from the builder before completion.
If you own your home and want to switch to a green rate, you may need a new BER. The old certificate may have run out, or the home may have been upgraded since. A BER assessment typically costs €225 to €400 and takes a few hours on site. Find an assessor on SEAI's register and ask for a quote. Our guide on BER ratings explained covers what the assessor checks.
The assessor also gives you an advisory report. It lists the works that would lift the rating, in order of effect. That is the starting point for a retrofit.
Green top-ups for retrofits
Some lenders offer a green top-up: extra borrowing on your mortgage, at a lower rate, for energy works. Insulation, windows, a heat pump and solar panels are the usual list. The lender normally asks for:
- A BER before the works, and a plan for the works.
- Quotes from registered contractors.
- A new BER after the works, in some cases, to keep the rate.
Our top-up guide explains how a top-up works and what the lender checks.
SEAI grants can cover part of the same works. The grants for insulation, heat pumps and solar panels are listed on SEAI's page. A grant reduces what you borrow, and a top-up covers the rest. Our guide on SEAI grants for home buyers lists them.
Switching to a green rate
If your home is B3 or better and your current rate is not green, you may be able to move. There are two routes:
- Ask your own lender to move you to its green rate. If you are on a fixed rate, a breakage fee can apply. Ask for the figure in writing.
- Switch to another lender's green rate. That needs a solicitor (check the Law Society's register) and a valuation. See what a conveyancing solicitor does and our switching guide.
Since 24 March 2026, under the Consumer Protection Code 2025, your lender must tell you what you could save on a lower rate it offers. That includes a green rate if your home qualifies. Our changes page logs the rule.
What a green mortgage is not
A green mortgage is not a grant and it is not a separate loan. It is the same mortgage at a lower rate. The home must meet the threshold on the day the lender checks. The rate applies for the fixed period, and the lender's terms say what happens after.
It also says nothing about the home's condition. A B3 rating means the home holds heat well. It does not mean the roof is sound. A survey is a separate matter.
Where this leaves you
Find the BER of the home you are buying or own, and check it against the threshold on our green rates page. If the home needs a new certificate, get quotes from assessors on SEAI's register. The switching journey takes you through the move to a lower rate step by step.
Questions people ask
What BER do you need for a green mortgage?
Most lenders ask for a BER of B3 or better, which means A1, A2, A3, B1, B2 or B3. Each lender sets its own threshold, and our green rates page shows the one each lender applies.
How much lower is a green mortgage rate?
In the indicative figures on our rates page, the green rate sits about 0.2 to 0.25 of a percentage point below the same lender's standard fixed rate. On €300,000 over 30 years that is about €33 a month.
Can I get a green mortgage on a second-hand house?
Yes, if its BER is within the lender's threshold, usually B3 or better. The seller must give you the BER certificate. Many older homes are below B3 unless they have been upgraded.
Does a new build qualify for a green mortgage?
Almost always. New homes built to current regulations are rated A, so they meet every lender's threshold. The builder provides the BER certificate before you close.
What is a green top-up?
A green top-up is extra borrowing on your mortgage, at a lower rate, for energy works such as insulation or a heat pump. Some lenders offer one. The lender usually asks for a plan and a BER before and after the works.