An Energy Performance Certificate (EPC) is a legal document that rates a property's energy efficiency on a scale from A (most efficient) to G (least efficient). In England and Wales, an EPC is required by law before you can sell or let a property, and mortgage lenders increasingly use the rating as part of their assessment. If you are buying, selling, or renting, understanding what an EPC is and what it means for your property is essential.
Contents
What an EPC is
An EPC is produced by a qualified Domestic Energy Assessor (DEA) following a physical inspection of the property. The assessor looks at the construction, insulation, heating systems, windows, and other factors that affect energy use, and calculates both the current energy efficiency rating and a potential rating if recommended improvements were made.
The certificate includes a current rating, a potential rating, the estimated annual energy costs for the property, and a list of cost-effective improvements with their estimated impact. It is lodged on the national EPC register and is publicly searchable — anyone can look up whether a property has a current EPC using the government's online register.
What the ratings mean
EPC ratings run from A to G, where A is the most energy efficient and G is the least. Each band corresponds to a score out of 100:
| Rating | Score | What it typically means |
|---|---|---|
| A | 92–100 | Highly insulated, often new build or heavily retrofitted. Very low energy bills. |
| B | 81–91 | Well insulated, modern heating. Lower-than-average bills. |
| C | 69–80 | Average to good. Most modern UK homes fall here. |
| D | 55–68 | Below average. Common in older properties. Some draughts or heating inefficiency. |
| E | 39–54 | Poor. Higher bills, likely older heating system, limited insulation. |
| F | 21–38 | Very poor. Properties at F or below cannot legally be let in England and Wales. |
| G | 1–20 | Extremely poor. Cannot be let; likely to require significant work before sale. |
The average EPC rating for UK homes is currently D. New builds are typically rated B or above. Properties built before 1980 without significant improvement work often fall in the D–F range.
When you need one
You are legally required to have a valid EPC in the following situations:
- Selling a property — the EPC must be obtained before the property is marketed and provided to potential buyers.
- Letting a residential property — landlords must have a valid EPC with a minimum rating of E before granting a new tenancy (with some exemptions for listed buildings and certain other properties).
- Building a new home — an EPC is required on completion.
- Making certain modifications — significant extensions or changes to heating systems may require an updated EPC.
Buyers are not legally required to obtain an EPC themselves — the seller must provide one. However, if the existing EPC has expired (certificates last ten years), a new one is needed before the property can be marketed.
How long an EPC lasts
An EPC is valid for ten years from the date it is issued, unless significant work is carried out that would materially change the rating. If you are buying a property, check the date on the existing EPC — a certificate from 2015 or earlier may not accurately reflect the current state of the property if improvements have been made, and a new one will be needed if significant work has been done or the existing one has expired.
You can check whether a property has a current EPC and view its rating free of charge using the government's EPC register at gov.uk/find-energy-certificate.
EPCs and mortgages
Mortgage lenders are increasingly interested in EPC ratings, and this is an area that is changing. A few things to know for 2026:
- Green mortgage products — many UK lenders offer preferential rates for properties rated A or B, sometimes called "green mortgages." The discount is typically small (0.1–0.2% off the rate) but can add up over a 2 or 5 year fixed period.
- Rental sector rules tightening — the government has proposed requiring all rental properties to achieve a minimum EPC rating of C by 2030. While legislation has not yet been confirmed, this is moving. Landlords buying investment properties should factor in the cost of reaching C on lower-rated properties.
- Buyer due diligence — a low EPC rating is a legitimate factor when assessing a property. A D or E rated home may be significantly cheaper to buy, but higher energy costs and the potential cost of improvement work should be factored into your affordability calculations. Our full cost of buying a house guide covers what to budget for beyond the headline price.
How to improve your EPC rating
The EPC itself will recommend specific improvements for the property, ranked by cost-effectiveness. Common improvements that raise ratings include:
- Loft insulation — often the highest-impact, lowest-cost improvement. An uninsulated loft losing heat through the roof can drag a rating down significantly. Government grants may be available through the Great British Insulation Scheme.
- Cavity wall insulation — for properties with cavity walls (most post-1920 construction), cavity insulation is typically cost-effective and can raise a rating by one or more bands.
- Upgrading the boiler — replacing an old G-rated boiler with a modern A-rated condensing boiler meaningfully improves the rating and reduces bills.
- Double glazing — replacing single-glazed windows with double or triple glazing improves both the rating and the property's warmth and noise insulation.
- Solar panels — can raise a rating significantly, particularly where the roof is south-facing, though the upfront cost is higher than the above options.
Before spending on improvements, obtain a new EPC assessment after each significant change rather than assuming the rating will automatically improve.
How to get an EPC
An EPC must be produced by an accredited Domestic Energy Assessor. You can find accredited assessors in your area through the government register, or use an established provider that covers the whole of the UK.
Affiliate link — we may earn a commission if you book via this link, at no cost to you.
A standard EPC assessment for a typical UK home typically costs £60–£120 and takes 30–60 minutes on site. Larger or more complex properties cost more. The certificate is then lodged on the national register and emailed to you, usually within 24–48 hours of the assessment.
If you are selling, instruct an EPC assessor as early as possible — the certificate must be available before marketing begins, and delays can hold up your sale timeline.
Last reviewed: July 2026
Next review due: October 2026