If you've made improvements to your rental property in the last few years — added insulation, upgraded the boiler, installed solar panels — you may already qualify for a better mortgage rate. You just haven't updated your EPC.
That's the finding from a Property118 study (May 2025): landlords are systematically missing opportunities to access cheaper green buy-to-let mortgage products because they've never commissioned a new EPC assessment after making energy-saving improvements. A reassessment costs £60–£120. The rate saving it unlocks can be worth hundreds of pounds per year, per property.
This article covers how green BTL mortgages work, which EPC rating you actually need, which lenders offer them, and whether the numbers stack up.
Have You Already Qualified Without Knowing It?
Before diving into which products exist, the most immediately actionable thing for most landlords is this: get an updated EPC if you've made any improvements since your current certificate was issued.
EPC ratings are based on a point-in-time assessment. If you added loft insulation three years ago but your EPC still reflects the 2020 state of the property, your certificate isn't telling lenders the full story. The same applies to boiler upgrades, double glazing replacements, or solar panel installation.
The process is straightforward: find an accredited energy assessor, book a reassessment, receive an updated certificate within a few days. If your property has crossed into a higher EPC band, you can use that certificate immediately when applying for or switching to a green mortgage product.
Check your EPC issue date at Find an Energy Certificate (gov.uk). If it's more than two years old and you've done improvement work since, a reassessment is worth the outlay.
How Green BTL Mortgages Work — The Two-Tier System
Green buy-to-let mortgages reward landlords for owning energy-efficient properties. But "energy efficient" means different things at different EPC levels, and the distinction matters.
Tier 1 — EPC C: Removing the Barrier
The most urgent financial impact of EPC ratings is at the lower end. Landlords with EPC D, E, F, or G properties are facing tightening lender criteria — with major banks increasingly refusing to remortgage properties below EPC C, or offering less favourable LTV ratios. We cover this in detail in our guide to buy-to-let mortgages and EPC C requirements.
Reaching EPC C doesn't unlock premium green mortgage rates at most lenders, but it removes the compliance barrier — you're no longer at risk of being refused at remortgage. Some lenders offer a modest green discount at EPC C: Barclays, for example, offers approximately 0.10% better rates at EPC C compared to EPC D and below (based on a 25% deposit product). That's real money — roughly £150 per year on a £150,000 mortgage — but it's a threshold benefit rather than a premium reward.
Tier 2 — EPC A or B: Unlocking the Real Green Rates
The dedicated green BTL mortgage products — the ones with meaningful rate discounts and cashback offers — predominantly require EPC A or B.
The Green Finance Institute (December 2025, cited by Which?) identified 31 green buy-to-let mortgage products across 28 providers. At this level, the typical benefits are:
- Rate reduction: 0.10%–0.30% better than equivalent standard BTL products
- Cashback: £250–£1,000 on some products at purchase or remortgage
- Fee discounts: reduced arrangement fees on selected products
On a £200,000 BTL mortgage with a 0.20% rate reduction, that's £400 per year saved — and for a portfolio landlord with five properties, £2,000 annually. These savings compound over a five-year fixed term.
Which Lenders Offer Green BTL Mortgages?
The green BTL market has grown significantly. Lenders with confirmed products include:
| Lender | EPC Required | Key Benefit | Notes |
|---|---|---|---|
| Barclays | A/B (new build primary focus) | Rate discount (~0.10%) | Green BTL product range |
| NatWest | A/B | Reduced 2yr/5yr fixed rate | Standard application process |
| HSBC | A/B | Lower rate tier | Check current product availability |
| Paragon Bank | A/B | Active green BTL range | BTL product guide updated March 2026 |
| Virgin Money | A/B | Lower rates for existing customers | New-build EPC A/B focus |
| Skipton Building Society | A/B | Rate discount | Specialist BTL lender |
| Bank of Ireland | A/B | Green BTL range | Varies by LTV and term |
Important caveat: Green mortgage rates and eligibility criteria change frequently. The table above reflects the market as of March 2026 but should not be used as a basis for application decisions. Always confirm current criteria directly with the lender or via a specialist buy-to-let mortgage broker.
Most of these products also apply to standard let properties and HMOs, though criteria for HMOs may differ — check individual lender guidelines.
Is the Maths Right? — Calculating the Real Benefit
Whether green mortgage savings justify upgrade costs depends on your starting point.
Scenario A: Reassessment only You added loft insulation two years ago. Current EPC: D (issued in 2022). Reassessment reveals: C, possibly B.
- Reassessment cost: ~£80
- If result is B: unlock green BTL product → 0.20% rate saving on £180,000 mortgage → £360/year
- Break-even: under 3 months. Net gain over 5-year fix: ~£1,720.
Scenario B: Upgrade to A/B from C Your property is currently EPC C. Upgrading to A/B requires solar panels + heat pump.
- Net cost after grants (£7,500 BUS + 0% VAT): approx. £8,000–£12,000 depending on property
- Rate saving: 0.20% on £180,000 = £360/year
- Break-even on mortgage savings alone: 22–33 years
- But — factor in: EPC compliance assurance to 2030, property value uplift (EPC A/B properties attract premium), running cost savings, and grant recouped portion
Scenario A is the easy win. Scenario B requires a longer view — the mortgage rate saving alone doesn't justify the upgrade cost, but when combined with compliance value and energy bill savings, the combined ROI improves significantly. If you're already planning to upgrade for the £10,000 cost cap or the 2030 deadline, the green mortgage benefit is an additional layer of return rather than the primary driver.
How to Access a Green BTL Rate
The process is the same as a standard remortgage — there's no special application track for green products.
- Commission a current EPC assessment if your existing one is over 2 years old or post-improvement
- Note your EPC rating and certificate number — you'll need these
- At your next remortgage date, ask your broker specifically to source green BTL products alongside standard products
- If your property is EPC A or B, request lenders on the Green Finance Institute tracker or Which? green mortgage list
- Factor in any early repayment charge (ERC) before switching products mid-term — the rate saving needs to exceed the ERC to make early switching worthwhile
- Use a specialist BTL broker — not all high-street mortgage advisers are familiar with green BTL product criteria
If your current deal has more than 18 months remaining and you'd face an ERC, hold the reassessment and improvement plans until closer to the renewal window. Green products will still be available — they're growing, not shrinking.
Frequently Asked Questions
Do I need to spend money on improvements to qualify for a green BTL mortgage?
Not necessarily. If you've already made improvements since your last EPC was issued, an updated assessment (£60–£120) may reveal you already qualify. Start there before planning any upgrades.
Is EPC C enough to get a green mortgage?
EPC C removes mortgage barriers — lenders will no longer refuse to lend. A modest rate discount may apply at some lenders (e.g. ~0.10% at Barclays). However, most dedicated green BTL products with meaningful rate reductions require EPC A or B.
Can I get cashback from my lender for improving my EPC?
Some lenders offer cashback (typically £250–£1,000) at remortgage for EPC A or B properties. Check individual lender criteria — not all products include this, and terms change regularly.
What if my EPC is A or B but my current deal isn't up for renewal?
Check your ERC before switching early. If the ERC is less than the rate saving you'd achieve over the remaining fixed term, early switching may make sense. Calculate this with a broker.
Do green mortgages apply to HMOs and multi-unit blocks?
Some lenders extend green products to HMOs, but criteria often differ from single-let properties. Paragon and specialist HMO lenders are the best starting point. Confirm with the lender directly.
Next steps: Use our property cost estimator to model upgrade costs and check whether the route to EPC A or B is financially realistic for your property type. If you're considering the £7,500 Boiler Upgrade Scheme grant or solar panels as part of your EPC improvement strategy, those articles cover the economics in detail.