UK SRS S2 + S1 standards: Climate-specific and general framework

UK SRS S1 and S2 overview

The UK Sustainability Reporting Standards (UK SRS) consist of two standards: UK SRS S11 establishes the General Requirements for Disclosure of Sustainability-related Financial Information; UK SRS S21 sets out the Climate-related Disclosures specifically.

Both were published by the Department for Business and Trade1 on 25 February 2026 alongside the Government Response to the consultation.2

The relationship between the two standards is fundamental: S1 is the framework; S2 is its first application.

UK SRS S11 establishes the materiality principles, four-pillar architecture, connectivity principle, and disclosure framework that apply to ALL sustainability topics.

UK SRS S21 then applies these principles specifically to climate-related risks and opportunities.

Future topic-specific standards (S3, S4, etc.) — if and when ISSB issues them and the UK adopts — would follow the same pattern, applying S1's framework to additional sustainability themes.

Currently, UK SRS S3 does not exist.

How UK SRS S1 and S2 work together

The two-standard architecture allows entities to start with climate (using UK SRS S21) while building capabilities for broader sustainability reporting under UK SRS S1.1

Three coordination mechanisms operate between the standards:

• Materiality framework — both use the same financial materiality threshold
• Four-pillar architecture — Governance, Strategy, Risk Management, Metrics & Targets
• Connectivity principle — sustainability disclosures connected to financial statements

Under FCA CP26/53, in-scope listed companies disclose information about their climate-related risks and opportunities in accordance with UK SRS S2 and must apply the specific provisions in UK SRS S1 as relevant to those climate-related disclosures.

UK SRS S2 (excluding Scope 3 emissions) is proposed mandatory from 1 January 2027; broader UK SRS S1 application is on a comply-or-explain basis from 1 January 2029.

Sequencing — start with S2, build to S1

For most UK entities approaching UK SRS, the practical sequencing is to start with UK SRS S2 (climate)1 and build capability over time for broader UK SRS S1 (general sustainability)1 coverage.

Reasons for this sequencing:

• TCFD continuity — existing disclosure overlaps with UK SRS S2
• Mandatory timeline — S2 from 2027, S1 comply-or-explain from 2029
• Climate materiality — typically passes financial threshold for most companies
• Data infrastructure — climate emissions data more mature
• Assurance availability — practitioner experience greater on climate

Four-pillar architecture across both standards

UK SRS S11 and UK SRS S21 share the TCFD four-pillar architecture7.

The table summarises how each standard applies the pillars:

Each pillar requires disclosure of current state and forward-looking information1, with quantitative metrics where possible and qualitative explanation where quantification is not yet feasible.

The connectivity principle1 requires that the disclosures align with financial statement timing, scope, and recognition principles.

For detailed coverage of each pillar across both standards, see UK SRS Four Pillars.

For the individual standards, see UK SRS S1 Materiality and UK SRS S2 Deep Dive.

For a comprehensive overview of all ESG reporting requirements UK, including how UK SRS fits with SECR and ESOS, see our complete guide.

Six UK amendments to IFRS S1 and S2

The UK SRS1 retains close alignment with IFRS S14 and IFRS S25 with six specific UK amendments — verified against the Government Response to the UK SRS Consultation2 and Linklaters' analysis11.

Amendment 1 — SASB Industry-based Guidance: "shall" → "may"

Paragraphs 12, 23, and 32 of IFRS S25 state that entities "shall refer to and consider" the applicability of the Industry-based Guidance on Implementing IFRS S2 (the SASB Industry-based Guidance).

In each corresponding paragraph of UK SRS S21, "shall" has been amended to "may"2.

Practical effect2: UK SRS S2 entities are expected to disclose industry-relevant metrics but are NOT required to use the SASB-based guidance specifically.

The amendment provides flexibility for UK entities to use alternative industry-relevant metrics where appropriate.

Amendment 2 — Removal of effective dates and time references

UK SRS S11 and UK SRS S21 do not contain effective date provisions.

Time references for temporary reliefs have also been removed11.

Rationale and effect2:

• Effective dates will be set when mandatory reporting requirements are introduced — via FCA Listing Rules [3] for listed entities; via Companies Act 2006 [14] amendments under MCR Strand 2 [2] for private entities
• Standards are available for voluntary use immediately without effective-date complications
• Time references for temporary reliefs (non-climate reporting relief, Scope 3 relief) have been removed; the standards no longer specify duration of relief application
• Reliefs may be re-introduced with specific durations when mandatory reporting requirements are introduced

Amendment 3 — Compliance statement provisions

UK SRS S11 includes provisions limiting the ability to make compliance statements OR requiring that additional information is included in compliance statements when an entity is relying on reliefs11.

The amendments affect paragraphs E3, E4, and E6 of UK SRS S12:

• Paragraph E3 — relief for non-climate reporting (allowing entities to focus on climate disclosure in initial reporting)
• Paragraph E4 — comparative information requirements; paragraph E4(b) amended specifically to require comparative information only in the second annual reporting period in which the relief no longer applies
• Paragraph E6 — compliance statement requirements when reliefs are applied

Practical effect: entities relying on reliefs must provide additional disclosure about which reliefs are being applied; entities not relying on reliefs may make full compliance statements with UK SRS1.

Amendment 4 — Removal of delayed sustainability reporting relief

UK SRS1 removes the IFRS S14 ability for entities to report sustainability disclosures AFTER they have published their financial statements.

Sustainability disclosure must be published WITH the financial statements11.

Rationale2:

• Connectivity principle — sustainability disclosure connectivity with financial statements requires same-time publication
• Existing UK climate-related financial disclosure requirements under Companies Act 2006 section 414CB [14] already require same-time publication with the annual report
• TCFD disclosure under existing FCA Listing Rules [9] (LR 9.8, to be replaced) requires publication with the annual financial report
• UK entities are well-positioned for same-time publication given existing reporting infrastructure

This amendment strengthens the connectivity principle and aligns UK SRS1 with existing UK reporting practice.

Amendment 5 — Paragraph B59A (financed emissions reporting flexibility)

UK SRS S21 includes a new paragraph B59A that allows financial institutions to report financed emissions from a DIFFERENT reporting period than the entity's own emissions, provided that additional disclosures are made11.

Practical effect2:

• Recognises the inherent data lag in financed emissions calculation — financial institutions typically receive investee/borrower emissions data 12-18 months after the relevant period
• Allows reporting of financed emissions data lagged by one reporting period without the entity being non-compliant
• Additional disclosures required: specifically about the time lag, the reporting period covered, and methodology used
• Practical accommodation that maintains substantive disclosure while reflecting data availability constraints

This amendment is particularly relevant for banks, insurers, asset managers, and other financial institutions in scope of UK SRS S21.

See UK SRS for Financial Services for sector-specific coverage.

Amendment 6 — Incorporation of ISSB December 2025 IFRS S2 amendments

The ISSB published targeted amendments to IFRS S26 in December 2025.

UK SRS S21 incorporates these amendments (except the effective date and transition provisions, which are not relevant given UK SRS's own structure under Amendment 2)2.

The ISSB December 2025 amendments6 cover four targeted topics:

• Allowing an entity to limit the measurement of Category 15 Scope 3 GHG emissions to only "financed emissions" (a narrower scope than the general Category 15 definition)
• Permitting an entity to select an industry-classification system for disaggregating financed emissions (alternative to the IFRS-prescribed approach)
• Expanding the jurisdictional relief from using the GHG Protocol Corporate Standard — applies if an entity (in whole or in part) is required to use a different method for measuring GHG emissions
• Introducing a new jurisdictional relief allowing an entity to use global warming potential (GWP) values other than the values currently required by the GHG Protocol

The UK Sustainability Disclosure Technical Advisory Committee (TAC) reviewed the ISSB amendments in January 2026 and recommended their inclusion in UK SRS S22.

The TAC's written recommendations were sent to DBT on 26 January 2026; UK SRS S2 incorporates the amendments accordingly.

For detailed comparison of UK SRS and IFRS S1/S2 including these amendments, see UK SRS vs IFRS S1/S2.

Mandatory timeline

UK SRS S1 and S21 are available for voluntary use immediately from 25 February 2026.

The path to proposed mandatory application:

• 30 January 2026 — FCA published CP26/5 [3]
• 20 March 2026 — CP26/5 consultation closed (209 responses received)
• Autumn 2026 — FCA Policy Statement expected, finalising UK Listing Rules [9]
• 1 January 2027 — UK SRS S2 proposed mandatory for UKLR 6/14/15/16/22 (excluding Scope 3); UKLR 14/15 subject to flexible disclose-home-jurisdiction approach
• 1 January 2028 — Scope 3 emissions disclosure becomes comply-or-explain (subject to deferral availability)
• 1 January 2029 — UK SRS S1 comply-or-explain (broader sustainability topics)
• 2026-2028 (anticipated) — MCR Strand 2 consultation [2] and possible Companies Act 2006 [14] amendments to extend application to economically significant private companies

The two-track timeline — FCA-led for listed companies; DBT-led for private companies — means UK SRS1 mandatoriness expands progressively over multiple years rather than at a single effective date.

See UK SRS Timeline for detailed coverage.

Frequently asked questions