UK SRS: Mandatory Sustainability Reporting from 2027 — What Your Business Needs to Do Now

The End of Fragmented Reporting

For years, UK businesses have navigated a patchwork of sustainability disclosure requirements — SECR for energy and carbon, TCFD-aligned reporting for climate risk, and various voluntary frameworks like GRI and CDP. That era is ending.

On 25 February 2026, the Department for Business and Trade published the final UK Sustainability Reporting Standards — UK SRS S1 (General Requirements) and UK SRS S2 (Climate-related Disclosures). These are the UK-endorsed versions of the ISSB's global baseline standards, IFRS S1 and IFRS S2, and they will become the single, legally enforceable framework for sustainability reporting in the UK.

The FCA published Consultation Paper CP26/5 in March 2026, proposing to make UK SRS S2 mandatory for UK-listed companies for financial years beginning on or after 1 January 2027. This is not a distant prospect — it is eight months away.

Who Is Affected and When?

The FCA's proposed phasing is as follows:

Even if your company is not directly in scope for 2027, the ripple effects are immediate. Listed companies reporting Scope 3 emissions will need to collect carbon data from suppliers across their value chain — meaning SMEs and mid-caps will start receiving data requests from major customers within the next 12 months.

What UK SRS Actually Requires

UK SRS S2 is built on the four pillars of the TCFD framework — governance, strategy, risk management, and metrics/targets — but goes significantly further in several areas:

Scenario analysis: Companies must disclose how they have used climate-related scenario analysis to inform their strategy. This is no longer a "comply or explain" recommendation — it is a mandatory requirement. The scenarios must cover a range of plausible climate futures, including at least one scenario consistent with the goals of the Paris Agreement.

Transition plans: If a company has set a climate-related target (including net zero targets), UK SRS S2 requires detailed disclosure of the transition plan, including interim milestones, capital allocation plans, and how the plan is integrated into business strategy and financial planning.

Industry-specific metrics: UK SRS incorporates the SASB industry-based standards, meaning companies must disclose sector-specific sustainability metrics. For a housebuilder, this includes embodied carbon in materials and energy efficiency of completed homes. For a manufacturer, it includes process emissions intensity and water consumption. This is not generic boilerplate — it requires granular, operational data.

Financial connectivity: One of the most significant changes is the requirement for sustainability disclosures to be "connected" to the financial statements. Companies must explain how climate-related risks and opportunities have affected, or are expected to affect, their financial position, financial performance, and cash flows. This means your sustainability team and finance team need to be working from the same data.

How UK SRS Differs from TCFD

If your company already reports under TCFD, you have a meaningful head start — but UK SRS is not simply TCFD with a new name. Key differences include:

• Legal enforceability: TCFD-aligned reporting in the UK was largely "comply or explain". UK SRS S2 will be mandatory and subject to FCA enforcement.
• Scope 3 specificity: TCFD recommended Scope 3 disclosure where material. UK SRS S2 will require it from 2028, with detailed category-level reporting based on the GHG Protocol.
• Quantitative targets: UK SRS requires disclosure of quantitative climate targets, the base year, interim milestones, and whether targets are science-based and validated by a third party.
• Cross-referencing: UK SRS requires that sustainability disclosures reference the specific financial statement line items affected, creating a direct audit trail between climate risk and financial impact.
• Industry metrics: TCFD did not mandate industry-specific metrics. UK SRS, through its adoption of SASB standards, does.

The Scope 3 Challenge

For most businesses, Scope 3 emissions — those arising from the value chain rather than direct operations — represent 80–95% of total greenhouse gas emissions. They are also, by far, the hardest to measure accurately.

When Scope 3 reporting becomes mandatory in January 2028, companies will need to:

1. Map all 15 categories of Scope 3 emissions defined in the GHG Protocol Corporate Value Chain Standard.
2. Determine which categories are material to their business (most companies find 3–5 categories dominate).
3. Collect primary data from key suppliers where possible, rather than relying solely on spend-based estimates.
4. Establish year-on-year tracking with consistent methodology to demonstrate progress.

This is a data infrastructure challenge as much as a sustainability one. Companies that begin building supplier engagement programmes and data collection systems now will be in a far stronger position than those that wait until Q3 2027.

Six Practical Steps to Prepare

1. Run a gap analysis against UK SRS S2 now. Compare your existing TCFD or sustainability disclosures against the full requirements of UK SRS S2. Identify gaps in scenario analysis, financial connectivity, industry metrics, and quantitative target disclosure. This gives you a clear work programme for the next eight months.
2. Align your sustainability and finance teams. The "financial connectivity" requirement means climate risks must be reflected in financial planning. This requires joint working between sustainability leads, CFOs, and financial controllers — not a siloed sustainability report produced after year-end.
3. Start your Scope 3 baseline now. Even though Scope 3 isn't mandatory until 2028, the first year of reporting requires a base year. Starting your Scope 3 measurement now gives you a full financial year of data before the obligation kicks in.
4. Engage your supply chain. Write to your top 50 suppliers requesting carbon data. Many will not have it yet — and that's fine. The act of asking starts the process and demonstrates supply chain engagement that UK SRS expects you to disclose.
5. Review your climate targets. If you have a net zero target, UK SRS requires detailed disclosure of the transition plan, interim milestones, and capital allocation. Vague commitments without measurable pathways will be exposed under the new framework.
6. Get specialist support early. The intersection of ISSB methodology, FCA regulation, and sector-specific SASB metrics is technically complex. Engaging an expert now — when firms have capacity — is more cost-effective than scrambling in Q4 2026 when demand surges.

The Bigger Picture: UK SRS and the Global Reporting Convergence

UK SRS sits within a broader global convergence of sustainability reporting. The EU's Corporate Sustainability Reporting Directive (CSRD) — using the European Sustainability Reporting Standards (ESRS) — is already in effect for large EU companies. The ISSB standards (on which UK SRS is based) have been adopted or endorsed in over 30 jurisdictions worldwide.

For multinational businesses, this means sustainability reporting is rapidly becoming as standardised and mandatory as financial reporting. The companies that build robust data infrastructure and governance processes now will have a durable competitive advantage — not just in compliance, but in investor confidence, supply chain resilience, and access to sustainable finance.