Hundreds of UK landlords who’ve invested in energy efficiency upgrades could be missing out on cheaper green mortgage deals, new research from Paragon Bank has revealed. The reason? Many haven’t ordered new EPC assessments since completing their improvement works—potentially costing them access to better interest rates and more competitive remortgage offers.

Paragon’s latest report, Improving Standards and Sustainability in PRS Properties, surveyed more than 500 landlords. It found that 57% had not commissioned an updated EPC after improving their properties, meaning these landlords may still be listed with outdated, lower ratings that prevent them from benefiting from lender incentives tied to EPC bands A–C.

“We were one of the first lenders to launch green mortgages, offering lower rates for properties with EPC ratings of A–C, incentivising landlords to purchase homes with better energy efficiency,” said Louisa Sedgwick, Managing Director of Mortgages at Paragon Bank.

Landlords making upgrades, but missing the final step
Although a growing number of landlords have taken steps to upgrade their properties—such as installing insulation, switching to more efficient boilers, or improving windows—the research shows a disconnect between action and paperwork.

Only 28% of landlords said they had reassessed their EPC rating after works were completed. Of those, most saw an improvement. Just 14% said their EPC stayed the same.

This administrative oversight could be costing landlords dearly. Paragon’s green mortgage rates are available not just for purchases but also for remortgages—making EPC reassessment a potentially profitable step, especially during a climate of rising interest rates.

“These rates are also available on remortgages,” Sedgwick noted, “so we’d encourage landlords to reassess their properties following any energy focused upgrades because they could be eligible to take advantage of lower pricing.”

Jason Wells, a landlord from Nottingham, had a similar experience. “I’d spent around £7,000 across two of my houses—mostly insulation and new radiators,” he said. “It didn’t cross my mind that I needed to update the EPC to get a better mortgage rate. My broker had to spell it out for me. Once I got the reassessments done, both properties went from D to B, and I saved 0.6% on a new fixed-rate deal. Not bad for an extra £120 spent on EPC checks.”

Government proposals risk rental market strain
A second study by Pegasus Insight, also commissioned by Paragon, revealed broader challenges across the private rented sector (PRS). Of the 900 landlords surveyed, 60% said they own at least one property rated EPC ‘D’, and 25% hold one or more properties rated E, F or G.

Altogether, 48% of the average landlord’s portfolio falls short of the EPC ‘C’ rating proposed in the Government’s recent consultation on minimum energy standards for the PRS.

The Government had initially proposed that all new tenancies should meet EPC ‘C’ by 2025, with existing tenancies expected to comply by 2028. However, that timeline has since been thrown into question, following concerns over cost, feasibility, and unintended consequences.

“This research aligns with Government data highlighting how millions of properties will need to be upgraded to meet the proposed new minimum energy efficiency standards,” said Sedgwick. “As a result, we believe the 2030 target for all rental properties is unrealistic and could exacerbate the undersupply of homes for tenants.”

Paragon has formally responded to the consultation, calling on the Government to abandon its hard 2030 target in favour of a phased rollout between 2030 and 2035, allowing landlords the time—and financial stability—to implement changes gradually.

Forward-thinking landlords
While the looming EPC requirements pose a challenge, they also present a golden opportunity for proactive landlords. Those who invest wisely now, track their upgrades, and reassess their EPC ratings stand to benefit not just from green mortgage discounts, but from increased tenant appeal and long-term capital gains.

However, the key is follow-through. Without up-to-date certification, many landlords may be leaving money on the table—despite already spending thousands to modernise their properties.

With energy standards on the Government’s agenda and mortgage costs under intense scrutiny, landlords who understand the system—and use it to their advantage—will be best placed to thrive in the years ahead.