If you’re applying for a mortgage, there’s one often-overlooked document that’s becoming increasingly important: the Energy Performance Certificate (EPC).

While traditionally seen as just a legal requirement when selling or letting a property, EPCs are now playing a bigger role in mortgage decisions, especially as lenders and the government push toward a greener housing market. Here’s what you need to know.

What is an EPC?

An Energy Performance Certificate rates the energy efficiency of a property from A (most efficient) to G (least efficient). It also provides recommendations on how to improve the property’s energy performance, along with estimated costs and potential savings.

EPCs are valid for 10 years and are a legal requirement for most homes when they’re sold or rented.

Why Lenders Care About EPC Ratings

Mortgage lenders are increasingly factoring EPC ratings into their affordability models, risk assessments, and product offerings. Here’s why:

  1. Energy Bills Affect Affordability
    A more energy-efficient home typically has lower running costs. For lenders assessing affordability, a property with low utility bills may leave more disposable income for the borrower, meaning they may be able to borrow more or qualify more easily.
  2. Green Mortgages Are on the Rise
    Many lenders now offer green mortgages, preferential rates for homes with EPC ratings of A or B. These products reward buyers for choosing energy-efficient homes and encourage greener choices in the property market.
  3. Future-Proofing Risk
    With the government’s net-zero targets and growing environmental regulation, homes with poor EPC ratings (especially E, F or G) may face legal or resale issues down the line. Some lenders are now wary of these properties, as they may devalue faster or be harder to let or sell.

EPCs and Buy-to-Let Mortgages

If you’re a landlord or buying a property to let, the EPC rating is especially important. Since April 2020, all rental properties in England and Wales must have an EPC rating of E or above (with some exemptions). Failure to comply can lead to fines of up to £5,000.

Looking ahead, proposed legislation could push this minimum up to a C rating, which would dramatically impact the rental market and mortgage eligibility, for thousands of properties.

Advice for Buyers and Homeowners

  • Check the EPC early in the buying process. It’s publicly available via the government’s EPC register.
  • Use the recommendations section to understand what improvements can be made — and what it might cost.
  • Consider the long-term value: A better EPC rating can not only unlock better mortgage deals but also increase a property’s resale appeal.