What are the UK Sustainability Reporting Standards?

Quick Answer: UK SRS (UK Sustainability Reporting Standards) are the UK government's official sustainability disclosure standards, comprising two standards: UK SRS S1 (general sustainability-related financial disclosures) and UK SRS S2 (climate-related disclosures). They are based on the ISSB's IFRS S1 and S2 standards, adapted for the UK context, and set out how companies should report sustainability risks and opportunities that could affect their financial performance. Reporting is currently voluntary but is expected to form the foundation of future mandatory requirements for listed companies from 2027.

What Are the UK Sustainability Reporting Standards (UK SRS)?

UK SRS are sustainability disclosure standards published in final form by the Department for Business and Trade on 25 February 2026, currently available for voluntary use. They consist of two standards: UK SRS S1, which covers general sustainability-related financial information, and UK SRS S2, which covers climate-related disclosures specifically.

Both standards build on the ISSB's IFRS S1 and IFRS S2, which the ISSB issued in 2023 to create a global baseline for sustainability reporting. The UK government adapted these for the domestic context through a formal endorsement process managed by the Department for Business and Trade, making targeted amendments where needed to fit UK regulatory and reporting architecture. The final standards also incorporate a set of targeted amendments the ISSB made to IFRS S2 in December 2025, including changes to industry classification requirements.

The core purpose of UK SRS is to give investors and financial markets consistent, comparable, and decision-useful sustainability information. The focus is on financial materiality: companies disclose sustainability risks and opportunities that could reasonably affect their cash flows, access to finance, or cost of capital over the short, medium, or long term. This is a narrower lens than the double materiality used by the EU's CSRD, a distinction covered further below.

What Do UK SRS S1 and S2 Require?

Both standards are structured around four disclosure pillars that UK companies will recognise from the TCFD framework: governance, strategy, risk management, and metrics and targets.

UK SRS S1 sets the overarching rules for sustainability-related financial disclosures. It asks companies to identify which sustainability topics are financially material, explain how those topics are governed and managed, and connect sustainability information directly to the financial statements. Where a climate or social risk is discussed in the narrative, S1 expects that risk to be visible in financial decisions, such as impairment assessments or cash flow projections, rather than treating it as a separate narrative exercise.

UK SRS S2 applies the same four-pillar structure specifically to climate. It requires companies to disclose how climate-related risks and opportunities, both physical risks (flooding, extreme heat) and transition risks (policy changes, technology shifts, shifting market demand), affect the business model and financial planning. Under S2, companies must disclose Scope 1 and Scope 2 greenhouse gas emissions, identify which Scope 3 categories are material to their operations, and report against those. Companies must also set out climate targets and explain how transition plans are being put into practice.

A one-year transitional relief allows companies to defer Scope 3 reporting to their second year of disclosure, giving time to build carbon footprint tracking processes before full reporting begins.

Is UK SRS Mandatory in the UK?

UK SRS reporting is not currently mandatory. The standards are available now for any UK entity that wants to adopt them voluntarily, but there is no legal requirement to do so yet.

That is expected to change. On 30 January 2026, the Financial Conduct Authority published Consultation Paper CP26/5, proposing that listed companies be required to report in line with UK SRS from specific future dates. Under the FCA's proposals, UK SRS S2 (climate disclosures) would become mandatory for in-scope listed companies from 1 January 2027. Scope 3 emissions would follow on a comply-or-explain basis from around 2028, using the one-year transitional relief described above, and the broader UK SRS S1 disclosures would follow on a similar comply-or-explain basis from around 2029. The consultation closed for responses on 20 March 2026, with final rules expected in autumn 2026, so these dates remain proposals rather than confirmed law until the FCA publishes its final policy statement.

Mandatory reporting is not expected to stop at listed companies. UK SRS sits within the government's Modernising Corporate Reporting programme, announced in October 2025, which is expected to consult later in 2026 on extending sustainability reporting requirements to private companies under the Companies Act. The government has also indicated it will review how UK SRS interacts with existing Streamlined Energy and Carbon Reporting (SECR) requirements, to reduce duplication for the many mid-market businesses currently required to report under both. Separately, the Financial Reporting Council has been asked to establish an interim register of sustainability assurance practitioners by mid-2026, laying the groundwork for third-party assurance once mandatory reporting begins.

How Does UK SRS Differ from CSRD?

The most important distinction between UK SRS and the EU's CSRD is the materiality standard each one applies. UK SRS uses single, financial materiality, in line with the ISSB approach: a sustainability issue only needs to be disclosed if it could reasonably affect the company's own financial position. CSRD, built on the European Sustainability Reporting Standards (ESRS), uses double materiality, requiring companies to disclose both financial impacts on the business and the business's impact on people and the environment.

CSRD's scope is also considerably broader in terms of disclosure detail, covering a wide range of environmental, social, and governance topic standards, compared to UK SRS's narrower focus on financially material sustainability risks. For UK-headquartered companies with meaningful EU operations, this can mean falling into scope of both frameworks, with CSRD generally the more demanding of the two to satisfy. Companies that get their carbon data right for one framework are, in practice, most of the way to satisfying the other, since both ultimately rely on the same underlying Scope 1, 2, and 3 emissions inventory built to the GHG Protocol.

Why Does UK SRS Matter for Carbon Accounting?

Whether or not a business falls into the FCA's initial scope, UK SRS signals the direction UK sustainability reporting is heading: financially grounded, comparable, and built on credible underlying data. The Scope 1, 2, and 3 disclosures at the heart of UK SRS S2 are only as reliable as the carbon accounting process behind them.

For companies that have not yet built a full-scope greenhouse gas inventory, UK SRS gives a clear, practical reason to start now rather than waiting for mandatory rules to apply. Seedling produces GHG Protocol-aligned footprints across Scopes 1, 2, and 3, with the documented assumptions and data sources that credible disclosure, under UK SRS, CSRD, or both, ultimately depends on. Businesses already reporting under SECR or preparing a PPN 006 Carbon Reduction Plan are typically closer to UK SRS readiness than they realise, since much of the underlying data collection overlaps.

Getting ahead of the voluntary window, rather than waiting for mandatory deadlines to force the issue, gives businesses more time to build a robust process and iron out data gaps before assurance requirements arrive.

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