SECR, ESOS or CBAM? Which UK Carbon Regulations Apply to Your Business

UK businesses face three main carbon and energy compliance schemes, each with different thresholds, deadlines and reporting demands. This guide sets out who each one applies to and what it asks for — and why the same measured energy data underpins all three.

SECR: annual energy and carbon reporting

Streamlined Energy and Carbon Reporting (SECR) requires large UK companies to publish their energy use, greenhouse gas emissions, an intensity metric, and energy-efficiency actions in their annual directors' report. A company is in scope if it meets at least two of: turnover of £36 million or more, a balance sheet of £18 million or more, or 250 or more employees. Quoted companies report regardless of size.

ESOS: four-yearly energy audits

The Energy Savings Opportunity Scheme (ESOS) requires large undertakings — broadly, 250 or more employees, or turnover above £44 million with a balance sheet above £38 million — to audit their energy use every four years and identify savings opportunities. Since Phase 3, participants must also publish action plans setting out which savings they intend to deliver, with annual progress updates. The Phase 4 compliance deadline is 5 December 2027.

CBAM: carbon pricing at the border

Carbon border adjustment mechanisms price the embodied emissions of traded goods. The EU's CBAM entered its definitive regime in January 2026 and affects UK exporters of covered goods to the EU; the UK's own CBAM applies from 1 January 2027 to imports in the aluminium, cement, fertiliser, hydrogen, iron and steel sectors. Unlike SECR and ESOS, CBAM is not a disclosure exercise — it is a financial liability calculated from emissions data, which makes the quality of that data a commercial question.

The common thread: measured data

All three schemes are, at root, demands for defensible energy and carbon numbers. Businesses that assemble those numbers annually from bills and spreadsheets do the work three times, inconsistently, under deadline pressure. Businesses that measure continuously at asset level produce SECR figures, ESOS evidence and CBAM data from the same source — with an audit trail attached.

• SECR: continuous measurement turns the annual report into an export, not a project.
• ESOS: asset-level data does the auditor's discovery work in advance — and proves whether the action plan delivered.
• CBAM: measured emissions per tonne of product is the difference between paying on your actual performance and paying on default values.

CarbonMeter produces all three from one platform, with data lineage built in. If you are unsure which schemes apply to you, we are happy to talk it through.