From E to B: Where The Rules for Commercial EPC in London Are Heading

England’s commercial letting rules now require an EPC rating of E or above, with tighter targets ahead. Getting a commercial EPC in London early keeps your property lettable, saleable, and refinanceable as the goalposts move.

Key Takeaways

• All privately rented non-domestic properties in England and Wales must hold an EPC rating of E or above; F and G ratings are illegal to let without a registered exemption.

• The government’s proposed pathway would raise the bar to C, then B by around 2030, and over 80% of commercial buildings currently fall below EPC B.

• Exemptions expire and don’t automatically transfer on ownership change, making a trailing score a real risk at refinancing or sale.

• The improvement cost cap sits at £10,000 per property, with spending from October 2025 counting toward it; early action stretches that budget further.

Every commercial building you let in England needs an energy rating, and right now the floor sits at E. If you hold stock rated F or G, you cannot legally let it without a registered exemption. From April 2023, all privately rented non-domestic properties in England and Wales must hold an EPC rating of E or above, and leasing a property rated F or G is prohibited for both new and existing tenancies. Owners seeking a commercial EPC in London should act before the rules tighten further.

The direction of travel points higher. The plan on the table would lift the bar for properties to C, then to B. Most older London offices are nowhere near a B today. So the gap between where a building sits and where the rules want it is worth thinking about now, and getting a commercial EPC in London done early puts you ahead of the curve.

What The Rules Say Right Now

Exemptions expire, and they are not always transferable to a subsequent owner. Exiting from the limited medical exemption, however, is a meticulous and high-risk portfolio strategy: every element of that exemption has an expiration date; ownership transfers don’t automatically pass free-and-clear through ownership changes; and inequities surrounding a part-owner or former control group member can create uncomfortable questions at a time of refinancing pressure or divestiture. A trailing score, regardless of how small the margin is, still deters buyers and lenders.

Why was B picked?

In 2021, the government consulted on a staged pathway: landing first at an interim milestone of EPC C, with a view to tightening requirements to B by 2030. Support was strong. The EPC B target received the support of 91 per cent of respondents, while a date of 2030 for implementation was backed by 86 per cent. The reasoning is carbon. Approximately one-third of emissions from the UK building stock come from non-domestic buildings.

The Timeline Nobody Can Pin Down

Here is the honest part. The final response from the government has not been published. The situation for privately rented properties not in domestic use is still being considered. Some industry commentary from late 2025 and early 2026 also suggests the timetable may be revisited, with expectations that EPC B would fall within the range of circa. 2030 to 2035 for some. As for the interim EPC C milestone, it’s also still uncertain if it will remain one of the components of the framework. The date may move. The destination probably will not.

What London Buildings Are Up Against

London’s commercial stock skews old. Recent British Property Federation analysis suggests more than 80% of commercial buildings across major English cities currently sit below EPC B. For offices, warehouses and retail units, upgrade work runs on long cycles. You cannot fix a building’s fabric the week before a deadline. There is also a cost cap to know about. The improvement cap has been confirmed at £10,000 per property, with expenditure from October 2025 counting towards it.

If your building falls below the required standard, planning energy-efficiency improvements early can help avoid compliance issues and protect asset value. Specialist EPC upgrade services can help identify practical measures to improve ratings and meet evolving requirements.

Bottom Line

Waiting for certainty carries its own cost. A building stuck below the line is harder to let, harder to sell, harder to refinance. Tenants ask about running costs before they sign these days, and a poor rating answers that question for them.

Next steps: book an assessment, find your band, and plan from there. The rules are heading one way, and buildings that move early keep their options open.