Every property sold or rented in England and Wales needs an Energy Performance Certificate. But what does that A-to-G scale actually mean for your wallet?
What is an EPC?
An EPC rates a property's energy efficiency on a scale from A (most efficient, score 92-100) to G (least efficient, score 1-20). The certificate also shows a "potential" rating — what the property could achieve with recommended improvements.
What the ratings mean in practice
The average UK home is rated D. Here's roughly what each band means for annual energy costs (based on a typical 3-bed semi):
| Rating | Score | Typical Annual Cost | Description |
|---|---|---|---|
| A | 92-100 | £500-800 | Exceptional — new builds, heat pumps, solar |
| B | 81-91 | £800-1,200 | Very good — well-insulated modern homes |
| C | 69-80 | £1,200-1,600 | Good — the 2028 rental minimum |
| D | 55-68 | £1,600-2,000 | Average — most UK homes sit here |
| E | 39-54 | £2,000-2,500 | Below average — needs work |
| F | 21-38 | £2,500-3,200 | Poor — significant improvements needed |
| G | 1-20 | £3,200+ | Very poor — expensive to heat |
Why EPCs matter when buying
A poor EPC rating isn't just about energy bills. It affects mortgage lending (some lenders penalise low ratings), resale value, and — for buy-to-let investors — the legal minimum standard. Getting a property from G to C can cost £10,000-25,000 depending on the work required.
Common improvements that boost ratings
- Loft insulation (270mm+) — often the cheapest, biggest gain
- Cavity wall insulation — if the property has unfilled cavities
- Double or triple glazing — replacing single-glazed windows
- Upgrading the boiler — from an old G-rated to a modern A-rated condensing boiler
- Solar panels — can push a C up to a B or even A
- Smart heating controls — relatively cheap for a small boost
How to check a property's EPC
You can look up any property's EPC for free on the government's EPC Register, or use our free EPC checker to search by postcode and see all certificates in an area.