Your Accountant Says You’re a Medium Company Now. SECR Disagrees.

In April 2025 the government raised the company size thresholds in the Companies Act by roughly 50%. The headlines wrote themselves: thousands of businesses reclassified downwards, less red tape, simpler accounts. If your turnover sits somewhere between £36 million and £54 million, your accountant may well have told you that you are now a medium-sized company.

Here is the part that got far less coverage: SECR did not move. The Streamlined Energy and Carbon Reporting rules still use the old limits. Being re-badged as medium for accounts purposes does not release you from carbon reporting.

Two tests, two different rulers

Since 6 April 2025, the general size thresholds for a medium company are turnover up to £54 million, a balance sheet up to £27 million and up to 250 employees.

SECR ignores those new numbers. For unquoted companies and LLPs, SECR applies if you exceed at least two of:

• £36 million turnover
• £18 million balance sheet total
• 250 employees

So a company with £45 million turnover and a £20 million balance sheet is medium for its accounts and still fully in scope for SECR. The two regimes now use different rulers, and the gap between them is exactly where businesses get caught.

Who this catches

The awkward zone is any company that exceeds two of SECR's old limits but sits under the new medium ceilings. Advisers estimate thousands of companies moved down a size category in 2025. None of them moved out of SECR.

If that is you, your directors' report still needs UK energy use, Scope 1 and 2 emissions, an intensity ratio, a comparison against last year, and a description of energy efficiency action taken. Filing without it is a compliance failure your auditors will flag.

One genuine escape hatch survives: if your UK energy use is 40 MWh or less in the reporting year, you qualify as a low energy user and only need to state that. Very few companies over £36 million turnover get anywhere near that threshold.

What to do this quarter

1. Run both tests separately. Size classification first, then the SECR test against the old £36m/£18m/250 limits. Do not let one answer stand in for the other.
2. Check the timing. The new size thresholds apply to accounting periods beginning on or after 6 April 2025, so the first affected year-ends are arriving now. Confirm which regime each open year sits under.
3. If you are in scope, get the data flowing early. SECR's pain is rarely the report; it is reconstructing a year of meter readings, fuel receipts and mileage at year-end. Live capture during the year turns the disclosure into an export.

The threshold change was sold as simplification, and for accounts it is. For carbon reporting it quietly created a class of companies that believe they have been let off and have not. Make sure you know which side of that line you are on before your auditors tell you.