Mandatory sustainability & GHG reporting requirements in the United Kingdom

Since Brexit, the UK runs its own corporate climate-reporting framework rather than the EU's CSRD and ESRS. The result is a layered system: most large UK companies already have to disclose energy and emissions, the largest also make climate-risk disclosures, and a new ISSB-based standard is being phased in for listed companies. The four threads below are the ones that matter most — and they increasingly draw on the same underlying GHG data.

1. SECR — Streamlined Energy & Carbon Reporting

SECR is the UK's core mandatory energy-and-carbon disclosure regime, implemented through the Companies (Directors' Report) and Limited Liability Partnerships (Energy and Carbon Report) Regulations 2018. It applies to:

• UK quoted companies of any size (those listed on a recognised exchange); and
• Large unquoted companies and large LLPs that meet at least two of three thresholds in a financial year: 250 or more employees, turnover of £36 million or more, or a balance-sheet total of £18 million or more.

In-scope companies must report, in the directors' (or energy and carbon) report: total energy consumption in kWh, Scope 1 (direct) and Scope 2 (purchased electricity) emissions, at least one intensity ratio, the methodology used, and the energy-efficiency actions taken in the year. Quoted companies report on a global basis; large unquoted companies and LLPs generally report UK energy use. Scope 3 is voluntary under SECR but increasingly expected by investors, customers and ratings. Low-energy users (under 40,000 kWh in the period) can claim an exemption from detailed disclosure but must state that they qualify.

2. Mandatory climate-related financial disclosures (TCFD-aligned)

Separately, the UK was the first G20 country to make TCFD-aligned climate-risk reporting mandatory in law. For accounting periods beginning on or after 6 April 2022, the largest UK companies and LLPs must publish climate-related financial disclosures in the Non-Financial and Sustainability Information Statement within the strategic report. Broadly, the regime captures:

• UK companies and LLPs with more than 500 employees and turnover above £500 million; and
• UK traded, banking and insurance companies (and certain AIM companies) with more than 500 employees.

These disclosures follow the four TCFD pillars — governance, strategy, risk management, and metrics and targets — and emissions metrics rest on a credible GHG inventory. Around 1,300 of the UK's largest entities fall in scope.

3. UK Sustainability Reporting Standards (UK SRS S1 & S2)

The UK SRS are the UK's endorsement of the ISSB's IFRS S1 (general sustainability disclosures) and IFRS S2 (climate-related disclosures), adapted with a small number of UK-specific amendments. The Department for Business and Trade published the final standards in February 2026. They are voluntary at present, but the Financial Conduct Authority is consulting (CP26/5) on requiring listed companies to report against them:

• Climate disclosures under UK SRS S2 proposed to become mandatory for in-scope listed companies for accounting periods beginning on or after 1 January 2027;
• Scope 3 emissions proposed on a comply-or-explain basis with a one-year transitional relief, so mandatory from periods beginning on or after 1 January 2028;
• final FCA rules expected in autumn 2026, capturing roughly 500+ UK-listed companies. The FCA has not, so far, proposed mandatory third-party assurance — but any voluntary assurance obtained must be disclosed in full.

For most UK companies the practical takeaway is that ISSB-aligned reporting is coming, and a Scope 3 inventory — the hardest part — is best started early.

4. EU CSRD reach into UK groups, and the UK SME picture

The UK is not in scope of the EU's CSRD, but it can still reach UK businesses two ways. A UK subsidiary or branch of an EU group may be captured because its EU parent is reporting; and a UK-headquartered (non-EU) group with substantial EU activity can be caught directly. Following the EU's Omnibus I simplification (in force March 2026), the non-EU trigger is broadly a group with around €450 million of net turnover in the EU plus a qualifying EU subsidiary (turnover above ~€200 million) or branch — with new-scope obligations applying to financial years from 1 January 2027. EFRAG estimates only around 150–200 UK companies remain in CSRD scope after Omnibus, far fewer than before, so most UK companies will report under the UK regime rather than CSRD.

The UK has no direct equivalent of the EU's voluntary VSME standard for small companies. In practice, UK SMEs are pulled into carbon accounting by supply-chain and finance pressure: larger SECR/TCFD-reporting customers and banks request Scope 1–3 data from their suppliers and borrowers. SMEs can also report voluntarily against UK SRS, or use a proportionate framework, to answer those requests. Either way, the data need is the same — a defensible greenhouse-gas inventory.

Thresholds, dates and the status of the UK SRS proposals can change, and the FCA consultation was still open as this page was written. Confirm the rules that apply to your company before relying on them.

How to comply: why carbon accounting software

SECR, TCFD-aligned disclosures and UK SRS S2 all rest on the same foundation: a greenhouse-gas inventory built on recognised methodology, with every figure traceable to its source. Spreadsheets rarely survive an audit or assurance review, and rebuilding the numbers each year for a different framework wastes time. Carbon accounting software solves this by giving you one auditable dataset that produces every output you need.

See how the carbon accounting and reporting modules turn one inventory into SECR, TCFD and UK SRS outputs — and how larger groups use enterprise carbon accounting to consolidate multiple entities.

Why CarbonTool for the United Kingdom

CarbonTool is built for the layered reality UK companies face — reporting under domestic rules today while preparing for ISSB-aligned UK SRS tomorrow, and answering supply-chain data requests in between. It pairs enterprise-grade framework depth with transparent pricing and a choice of how much you do yourself.

CarbonTool is used by companies from Romania and across Europe to the UK, the Middle East, Asia and the Americas — so a UK group with international entities can consolidate the whole organisation in one place, report in GBP and other currencies, and choose self-serve, done-for-you or white-label delivery. If CSRD also touches your group through EU operations, the same platform covers it; see our CSRD software for Europe guide. Compare plans on the pricing page.