Quick answer: A green mortgage gives you a lower interest rate if the property you're buying, building, or renovating has a strong BER (Building Energy Rating) — typically B or higher on the simplified A0–G scale in use since 24 May 2026 (B3 or higher on older certificates). All major Irish mortgage lenders now offer them, including AIB, Bank of Ireland, EBS, Haven, PTSB, and Avant Money — with rates starting from around 3.0%. By 2024, roughly 40% of all new mortgage lending in Ireland was through green mortgages.
What is a Green Mortgage?
A green mortgage is a standard mortgage with a discounted interest rate, offered specifically for energy-efficient properties. The more energy-efficient your home (measured by its BER certificate), the better the deal you may qualify for.
The logic is simple: energy-efficient homes cost less to run, which means homeowners have lower outgoings, making them statistically lower-risk borrowers. Lenders pass some of that reduced risk back to the buyer as a rate discount.
In practice, the discount is typically built in from the outset — you apply for the green mortgage at the preferential rate rather than switching to it later.
BER Rating — What You Need to Qualify
Most green mortgages in Ireland require the property to have a strong BER — usually B3 or higher on older certificates, which corresponds to B or higher on the simplified A0–G scale in use since 24 May 2026 (where A0 is the most efficient and G the least). One notable exception is Bank of Ireland's EcoSaver, which applies a sliding discount across the entire BER scale — the better the rating, the larger the discount — rather than setting a single B-grade cut-off.
Three routes to a green mortgage:
- Buying a home that already has a qualifying BER (B / B3 or better)
- Renovating (retrofitting) a property to bring it up to the green threshold
- Self-building a new home to a B-or-better standard (new builds are A-rated as standard)
Green mortgages are available to first-time buyers, movers (trading up or down), switchers (remortgaging), and self-builders.
BER and What It Means for Running Costs
Your BER certificate grades your home's energy performance from A0 (the most efficient, on certificates issued since 24 May 2026 — or A1 on older certificates) down to G (very poor). The grade is calculated based on the building's insulation, heating system, ventilation, and renewable energy features.
| BER Grade (from 24 May 2026) | Legacy equivalent | Energy Efficiency | Typical Annual Bills |
|---|---|---|---|
| A0 | (new top band) | Fossil-fuel-free, near-zero energy | Lowest |
| A | A1–A3 | Excellent | Low (€800–€1,200/yr est.) |
| B | B1–B3 | Good (green mortgage threshold) | Moderate |
| C | C1–C3 | Average | Moderate-high |
| D | D1–D2 | Below average | High |
| E–G | E1–G | Poor to very poor | Very high (€3,000–€5,000+/yr est.) |
A home rated B3 or above is well-insulated, typically has a modern heating system, and may include air-to-water heat pumps, solar PV panels, or mechanical ventilation with heat recovery (MVHR). Many new builds in Ireland are A-rated as standard under current building regulations.
Which Lenders Offer Green Mortgages?
All major Irish mortgage lenders offer green mortgage products:
| Lender | Product Name | From Rate | Notes |
|---|---|---|---|
| AIB | Green Fixed Rate | 3.00% | On Green 3yr Fixed, >50%–≤80% LTV |
| Bank of Ireland | EcoSaver Mortgage | Sliding discount | Up to 0.35% off for A-rated homes; discount varies by BER level |
| EBS | Green Fixed Rate | 3.20% | Green 4yr Fixed |
| Haven | Green Fixed Rate | 3.00% | Green 4yr Fixed |
| PTSB | Green Fixed Rate | 3.45% | Green 5yr Fixed, ≤60% LTV |
| Avant Money | Eco Rate | See avantmoney.ie | Check current rates at avantmoney.ie |
Rates as at May 2026. Always check current rates directly with lenders before applying.
Discounts vary between lenders and depend on your loan-to-value (LTV), fixed rate term, property BER rating, and other factors. Green mortgage rates are fixed — they are not available on variable rate products.
Pros and Cons of a Green Mortgage
Advantages: - Lower monthly repayments over the fixed rate term - Some of the most competitive headline rates on the Irish market - Available for new purchases, remortgages, and self-builds - Aligns mortgage affordability with lower energy running costs
Things to watch: - Green mortgages are not always the cheapest option — some standard fixed rate deals may be lower, particularly with cashback - Cashback offers may not be available on all green rate products - If your home's BER drops below B3 (e.g. after a period without upkeep), switching eligibility is affected - Fixed rate terms mean early repayment charges may apply if you switch before the term ends
Is a Green Mortgage Right for You?
If you are buying a home with a BER of B (B3 on older certificates) or higher, it is worth specifically comparing green mortgage rates alongside standard rates. Given that green mortgages can include some of the lowest fixed rates available, they are worth prioritising in your mortgage comparison.
If the property you want to buy is rated C or lower, it may be worth exploring a SEAI retrofit grant first. Bringing a property from C up to the green threshold (B) through cavity wall insulation, attic insulation, and a heat pump is increasingly achievable — and could unlock green mortgage eligibility while significantly reducing running costs.
When you are browsing listings, check each home's BER. Most property portals let you filter by BER rating, which is a quick way to find homes that already qualify for a green mortgage.
Common Questions
Q: Can I use a green mortgage to renovate a home that doesn't currently meet the BER threshold? Some lenders offer green mortgage products specifically for renovation — where the borrowing includes funding to bring the home up to the green threshold (B, or B3 on older certificates) or better. Check with individual lenders, as product structures vary: some require the BER certificate before drawdown, while others accept a conditional green rating.
Q: Do I need a new BER certificate if I'm buying a property that already has one? BER certificates are valid for 10 years. If the property already has a valid certificate showing B3 or higher, that is typically sufficient for the lender. If the certificate is expired or the property has had significant changes, a new assessment (by a registered BER assessor) is required.
Q: If I get a green mortgage now and then sell the property, can the new owner take advantage of the rate? No — green mortgage discount rates are personal to the borrower and the loan agreement. They are not transferable to a new owner. When the property is sold, the mortgage is closed. The buyer arranges their own financing.