The UK Sustainability Reporting Standards (UK SRS) were published by the Department for Business and Trade on 25 February 20261 and are available for voluntary use by any UK entity. The FCA's CP26/5 consultation3 proposes mandatory application for listed companies in UKLR categories 6, 14, 15, 16, and 22 from accounting periods beginning on or after 1 January 2027. This FAQ covers the most-searched questions in nine thematic clusters; each answer cross-links to detailed coverage on the topic.

UK SRS basics

Seven questions covering what UK SRS is, who publishes it, when it was published, and what makes UK SRS different from other reporting standards.

What is UK SRS?
UK SRS (UK Sustainability Reporting Standards) are UK-domesticated versions of the International Sustainability Standards Board's IFRS S1 and IFRS S2910, published by the Department for Business and Trade on 25 February 20261.

UK SRS S1 covers general requirements for disclosure of sustainability-related financial information; UK SRS S2 covers climate-related disclosures specifically.

See What is UK SRS? for cornerstone coverage.
Who publishes UK SRS?
The Department for Business and Trade (DBT) publishes UK SRS as the policy lead1.

The standards are based on IFRS S1 and S2 published by the International Sustainability Standards Board (ISSB)910 in June 2023, with six specific UK amendments accepted by the UK government2.

The Financial Reporting Council (FRC) publishes related sustainability assurance and accounting standards including ISSA (UK) 50007.

The FCA implements mandatoriness for listed companies through UK Listing Rules313.
When was UK SRS published?
UK SRS S1 and UK SRS S2 were published by DBT on 25 February 20261.

The exposure draft consultation ran from 25 June to 17 September 2025 and received 209 responses2.

The final standards are available for voluntary use by any UK entity from publication.
Does UK SRS S3 exist?
No.

Only UK SRS S1 (General Requirements) and UK SRS S2 (Climate Disclosures) have been published1.

No UK SRS S3 has been issued by DBT, and no S3 timeline has been announced.

The ISSB has not yet finalised a third sustainability standard either.

The two-standard structure (general requirements + climate) reflects the ISSB's current standards architecture.
What is the difference between UK SRS S1 and S2?
UK SRS S11 sets the GENERAL framework for sustainability-related financial information disclosure across all material sustainability topics (water, biodiversity, social, human rights, governance, etc.).

UK SRS S21 applies the same framework SPECIFICALLY to climate-related risks and opportunities (Scope 1, 2, 3 emissions; transition plans; scenario analysis; cross-industry climate metrics).

S1 is the umbrella; S2 is the climate-specific application.

See UK SRS S1 and UK SRS S2 for cornerstone coverage.
Is UK SRS the same as IFRS S1 and S2?
Substantively very close, with six specific UK amendments2.

Key differences:

(1) removal of first-year delayed reporting relief — climate disclosure must be published with financial statements1;

(2) SASB Industry-based Guidance "shall" → "may" — companies expected to disclose industry-relevant metrics but not required to use SASB-based guidance specifically;

(3) clarifications of materiality threshold;

(4) UK-specific terminology;

(5) adjustments to financed emissions provisions for UK financial institutions;

(6) other refinements addressing UK reporting context.

See UK SRS vs IFRS S1/S2 for detailed comparison.
How does UK SRS relate to TCFD?
UK SRS S21 supersedes TCFD recommendations14 for in-scope listed companies under FCA CP26/53 from 1 January 2027.

TCFD provided the four-pillar framework (Governance, Strategy, Risk Management, Metrics and Targets) that UK SRS S2 builds on; UK SRS S2 adds more prescriptive requirements including mandatory Scope 3 disclosure (subject to deferral), quantitative scenario analysis, cross-industry metrics, and integration with financial statements connectivity.

See UK SRS vs TCFD for the detailed evolution comparison.

Standards content

Six questions covering what UK SRS S1 and S2 actually require — the four pillars framework, materiality concepts, and the structure of the standards.

What are the four pillars of UK SRS?
UK SRS uses the TCFD four-pillar framework114: (1) Governance — board oversight and management role; (2) Strategy — sustainability risks/opportunities and their effects on business model; (3) Risk Management — processes for identifying, assessing, and managing risks; (4) Metrics and Targets — quantitative disclosures including GHG emissions and progress against targets. Both UK SRS S11 and S21 organise their disclosure requirements under these pillars. See UK SRS Four Pillars for cornerstone coverage.
What is materiality under UK SRS?
UK SRS uses financial materiality (single materiality)1 — focused on sustainability information that could reasonably be expected to affect a company's cash flows, access to finance, or cost of capital. This differs from CSRD's double materiality (financial + impact). UK SRS materiality is dynamic — assessment must be revisited each reporting period. See UK SRS S1 Materiality for the three-way materiality comparison (UK SRS, CSRD, GRI).
What does UK SRS S2 require for climate disclosure?
UK SRS S21 requires disclosure across the four pillars covering: (1) Governance — board oversight, management role, expertise; (2) Strategy — climate-related risks and opportunities, business model impacts, scenario analysis (paragraph 22), transition plans (paragraph 14(a)(iii)), anticipated financial effects (paragraphs 14-15); (3) Risk Management — identification, assessment, and management processes; (4) Metrics and Targets — Scope 1, 2, 3 emissions, cross-industry climate metrics (paragraphs 29-30), climate-related targets (paragraphs 33-36). See UK SRS S2 for cornerstone coverage.
What is required for scenario analysis under UK SRS?
UK SRS S2 paragraph 221 requires quantitative climate scenario analysis assessing the resilience of business model and strategy under multiple climate scenarios. Scenarios should include at least one at the high end of warming (typically 3°C or higher) and one consistent with 1.5°C ambition. The IEA Net Zero Emissions by 2050 scenario14 (updated October 2025) is a common reference scenario. See UK SRS S2 for cornerstone coverage including scenario analysis requirements.
What about transition plans under UK SRS?
UK SRS S2 paragraph 14(a)(iii)1 requires disclosure of transition plans where a company has them — described as "disclose or explain". The TPT Framework five elements (Foundations, Implementation Strategy, Engagement Strategy, Metrics and Targets, Governance) provide the methodological reference. UK SRS does not require companies to HAVE a transition plan; it requires disclosure where one exists, or explanation of why not. See Transition Plans under UK SRS for detailed coverage.
How are Scope 1, 2, and 3 emissions defined under UK SRS?
UK SRS S21 adopts GHG Protocol Corporate Standard16 definitions: Scope 1 — direct emissions from owned/controlled sources; Scope 2 — indirect emissions from purchased electricity/heat/steam; Scope 3 — value chain emissions across 15 categories (purchased goods, capital goods, fuel-related, transport, waste, business travel, employee commuting, leased assets, processing, use of sold products, end-of-life, leased assets downstream, franchises, investments). Scope 3 disclosure is mandatory under UK SRS S2 from 1 January 2027 with first-year deferral and optional additional one-year deferral3. See Scope 3 under UK SRS for detailed coverage including the 15-category matrix.

Scope and application

Eight questions covering who is in mandatory scope, who can adopt voluntarily, listed vs unlisted companies, private companies, and overseas entities.

Who is in mandatory UK SRS scope?
Under FCA CP26/53, UK SRS S2 will be mandatory for listed companies in UK Listing Rules13 categories 6 (Commercial), 14 (Secondary), 15 (Depositary Receipts), 16 (Non-equity), and 22 (Transition) — for accounting periods beginning on or after 1 January 2027. UKLR 14 and 15 have a flexible approach where companies disclose home jurisdiction requirements rather than UK SRS itself3. UK SRS S11 applies on a comply-or-explain basis from 1 January 2029. See Who Must Comply with UK SRS? for cornerstone coverage.
Can any company adopt UK SRS voluntarily?
Yes — UK SRS1 is available for voluntary use by any UK entity from 25 February 2026 publication. Section 414CB(2A) designation5 applies to voluntary adopters as well as mandatory in-scope entities — using UK SRS S2 satisfies the climate-related financial disclosure requirements in section 414CB(1)-(5). The FRC Sustainability Reporting FAQ6 confirms voluntary application qualifies. Voluntary adoption is often considered by private companies anticipating MCR Strand 2 inclusion.
Does UK SRS apply to AIM-listed companies?
Not under FCA CP26/53. AIM is operated by the London Stock Exchange under AIM Rules — it is not a UKLR category. AIM-listed companies may voluntarily adopt UK SRS1 but are not in mandatory scope under CP26/5. AIM Rules may impose their own sustainability disclosure requirements separately.
Does UK SRS apply to private companies?
Not yet mandatorily. UK SRS1 is voluntary for private companies. The MCR Strand 2 consultation8 expected during 2026 will consider extending UK SRS application to economically significant private companies through Companies Act 2006 amendments4. Earliest realistic effective date: 2028 or later. See Private Companies and UK SRS for detailed coverage.
Does UK SRS apply to LLPs?
For listed LLPs in UKLR categories 6/14/15/16/22, yes under CP26/53. For unlisted LLPs, no mandatory application — voluntary adoption supported. The MCR Strand 2 consultation8 may extend application to large LLPs alongside private companies.
What about overseas companies listed in the UK?
Under CP26/53, UKLR 14 (Secondary listing) and UKLR 15 (Depositary Receipts) — which apply to non-UK companies with primary listing elsewhere — are subject to a flexible approach. These companies make a statement in the annual report setting out the sustainability reporting requirements applicable in their primary listing location, plus any voluntary standards adopted. Full UK SRS application is not required.
Does UK SRS apply to UK subsidiaries of overseas parents?
For unlisted UK subsidiaries — no mandatory application currently1; voluntary adoption supported. For listed UK subsidiaries — depends on UKLR category status. Group consolidated disclosure under parent-jurisdiction standards may satisfy stakeholder expectations even where UK SRS doesn't mandatorily apply. See UK SRS for Financial Services for financial services-specific guidance.
How does UK SRS apply to financial services?
Financial services entities are typically in scope of UK SRS through three sub-sectors per ICB classification: B60 (Banking), B61 (Insurance), and B62 (Other financial services). UK SRS S21 includes specific financed emissions provisions (paragraphs B59-B66) that apply to UK financial institutions. Asset managers and authorised firms may use UK SRS S1/S2 to cross-reference disclosure in their FCA SDR17 entity reports per UK SRS S1 paragraph 653. See UK SRS for Financial Services for detailed sector coverage.

Timeline and deadlines

Six questions covering CP26/5 status, mandatory application dates, comply-or-explain provisions, and MCR consultation timing.

When does UK SRS become mandatory?
UK SRS S21 mandatory application is proposed under FCA CP26/53 for listed companies in UKLR 6/14/15/16/22 from accounting periods beginning on or after 1 January 2027. UK SRS S11 applies on a comply-or-explain basis from 1 January 2029. Scope 3 emissions disclosure has comply-or-explain availability from 1 January 2028. See UK SRS Timeline for cornerstone coverage.
When will the FCA finalise CP26/5 rules?
The FCA expects to publish a Policy Statement on CP26/53 in autumn 2026, with final rules effective 1 January 2027. The consultation closed on 20 March 2026 with 209 responses received. FCA has authority to implement under FSMA 2000 without further parliamentary approval. See UK SRS Regulations for the broader regulatory framework.
When will UK SRS be mandatory for private companies?
No date confirmed. The MCR Strand 2 consultation8 expected during 2026 will consider extending UK SRS application to economically significant private companies through Companies Act 2006 amendments4. Earliest realistic effective date: 2028 or later, given consultation timelines and legislative passage. See Private Companies and UK SRS for coverage.
What does "comply or explain" mean for UK SRS?
Comply-or-explain provisions allow companies to either provide the relevant disclosure ("comply") or to explain why they have not done so ("explain"). Under CP26/53: UK SRS S11 applies on comply-or-explain basis from 1 January 2029; Scope 3 disclosure has comply-or-explain availability for first reporting year (1 January 2027 reporting) with optional additional one-year deferral. Explanation must be substantive — bare "not applicable" insufficient.
Can I adopt UK SRS early?
Yes. UK SRS1 is available for voluntary use immediately from 25 February 2026 publication. Early adopters benefit from section 414CB(2A) designation5 — using UK SRS S2 satisfies the climate-related financial disclosure requirements in section 414CB(1)-(5). Voluntary adoption is supported regardless of size or listing status6. Transitional reliefs available to mandatory in-scope companies are typically NOT available to voluntary adopters1.
What is the deadline for the first mandatory UK SRS S2 report?
For listed companies in mandatory scope under CP26/53 with calendar year accounting periods, the first mandatory UK SRS S2 report covers FY2027 — typically filed by mid-2028 (6 months for PLCs under Companies Act 2006 section 442). Reporting timeline aligns with annual report cycle. See UK SRS Compliance for implementation sequencing.

Implementation and practical steps

Five questions covering how to start, gap analysis, governance, data infrastructure, and time required.

How do I start UK SRS implementation?
Five priority steps:

(1) Confirm in-scope status — UKLR category for listed companies; voluntary adoption decision otherwise;

(2) Conduct gap analysis against current TCFD-aligned disclosure (where applicable) — UK SRS S21 is more prescriptive on Scope 3, scenario analysis, and connectivity;

(3) Establish board-level governance — UK SRS Governance pillar disclosure requires board oversight and management role;

(4) Plan Scope 3 data infrastructure — 12-18 months typical lead time for value chain data;

(5) Coordinate with assurance provider — ISSA (UK) 50007 effective 15 December 2026.

See UK SRS Compliance for cornerstone coverage.
What gap analysis is needed?
For existing TCFD-aligned reporters, the gap analysis should focus on:

(1) Quantitative scenario analysis under UK SRS S2 paragraph 221 — most TCFD-aligned reporters used qualitative scenario analysis;

(2) Scope 3 emissions disclosure across 15 categories under GHG Protocol16;

(3) Cross-industry climate metrics (paragraphs 29-30 of UK SRS S21);

(4) Anticipated financial effects (paragraphs 14-15);

(5) Connectivity with financial statements (UK SRS S1 paragraphs 21-24);

(6) Transition plan disclosure (paragraph 14(a)(iii)).

See UK SRS Compliance for the gap analysis framework.
What governance changes are needed?
UK SRS Governance pillar disclosure1 requires board-level oversight, management role definition, and competency disclosure.

Most large UK companies will need:

(1) Board-level sustainability/climate committee or designated board responsibility;

(2) Executive management responsibility identified;

(3) Reporting lines from operational climate teams to board;

(4) Director competency/training documented;

(5) Section 172(1) statement alignment4;

(6) Risk management integration.

UK SRS Governance is more demanding than TCFD on documentation and clarity.
How long does UK SRS implementation take?
For TCFD-aligned reporters: 6-12 months typical.

For non-TCFD reporters: 12-18 months typical.

Scope 3 data infrastructure is the long pole — 12-18 months to collect and validate value chain data.

Governance changes require 3-6 months for board engagement and committee structuring.

Materiality assessment requires 2-3 months.

Documentation and disclosure drafting requires 2-3 months.

Total program timeline: 6-18 months depending on starting point.

See UK SRS Compliance for sequencing.
What data infrastructure is needed?
UK SRS S21 data infrastructure typically requires:

(1) Scope 1/2 emissions data — facility-level energy and process emissions;

(2) Scope 3 emissions data — value chain across 15 categories per GHG Protocol16;

(3) Climate scenario analysis modelling — IEA NZE14, NGFS, IPCC scenarios;

(4) Anticipated financial effects modelling — linking climate risks to financial statement line items;

(5) Cross-industry climate metrics — capital deployment, internal carbon pricing, executive compensation linkages;

(6) Target tracking — quantitative metrics against published targets;

(7) Connectivity to financial statements — alignment with financial reporting timing and audit boundaries.

Disclosure content

Six questions covering specific disclosure requirements — emissions, scenario analysis, transition plans, materiality, anticipated financial effects, and cross-industry metrics.

What Scope 3 categories must be disclosed?
UK SRS S21 requires Scope 3 disclosure across all 15 GHG Protocol categories16 WHERE MATERIAL:

(Upstream) 1. Purchased goods and services, 2. Capital goods, 3. Fuel- and energy-related, 4. Upstream transportation, 5. Waste in operations, 6. Business travel, 7. Employee commuting, 8. Upstream leased assets;

(Downstream) 9. Downstream transportation, 10. Processing of sold products, 11. Use of sold products, 12. End-of-life treatment of sold products, 13. Downstream leased assets, 14. Franchises, 15. Investments.

Materiality assessment determines which categories disclosed.

See Scope 3 under UK SRS for the detailed matrix.
What scenarios are required?
UK SRS S2 paragraph 221 requires "use of climate-related scenario analysis to assess the resilience of the entity's strategy and its business model to climate-related changes, developments and uncertainties."

At least one scenario at the high end of warming and one consistent with 1.5°C ambition.

Common references: IEA NZE14 (1.5°C-aligned, updated October 2025 with 1.65°C temporary overshoot), NGFS Net Zero scenario (1.5°C-aligned), IPCC SSP scenarios.

See UK SRS S2 for cornerstone coverage including scenario analysis requirements.
What is required for transition plan disclosure?
UK SRS S2 paragraph 14(a)(iii)1 requires disclosure of "any climate-related transition plans" — where a company has them.

The standard is disclose-or-explain: companies disclose existing transition plans; companies without plans explain why not.

The Transition Plan Taskforce (TPT) Framework five elements (Foundations, Implementation Strategy, Engagement Strategy, Metrics and Targets, Governance) provide the methodological reference.

See Transition Plans under UK SRS for detailed coverage.
What is materiality under UK SRS?
UK SRS S11 uses financial materiality (single materiality) — focused on sustainability information that could reasonably be expected to affect a company's cash flows, access to finance, or cost of capital.

Materiality is dynamic — must be revisited each reporting period.

Differs from CSRD double materiality (financial + impact materiality) and GRI impact materiality.

See UK SRS S1 Materiality for three-way comparison.
What are anticipated financial effects?
UK SRS S2 paragraphs 14-151 require disclosure of the actual and ANTICIPATED financial effects of climate-related risks and opportunities on business model, financial position, financial performance, and cash flows.

Anticipated effects are forward-looking — covering short, medium, and long term horizons.

Section 46315 director safe harbour applies to good-faith disclosure of anticipated effects.

See UK SRS S2 for cornerstone coverage.
What are cross-industry climate metrics?
UK SRS S2 paragraphs 29-301 require seven cross-industry climate metrics:

(1) Scope 1, 2, 3 GHG emissions;

(2) Climate-related transition risks (amount and percentage of assets/business activities);

(3) Climate-related physical risks (amount and percentage of assets/business activities);

(4) Climate-related opportunities (amount and percentage of assets/business activities);

(5) Capital deployment for climate-related risks and opportunities;

(6) Internal carbon price (if used in decision-making);

(7) Executive remuneration linked to climate-related considerations.

Six questions covering the legal framework, section 414CB(2A) designation, director protection, enforcement, and section 172.

What is section 414CB(2A) designation?
Section 414CB(2A) of the Companies Act 200645 is the national reporting framework designation provision. DBT has designated UK SRS S21 under this section, confirmed by FRC FAQ February 20266. Entities applying UK SRS S2 satisfy the climate-related financial disclosure requirements in section 414CB(1)-(5)5 WITHOUT separate duplicate disclosure. The designation applies whether application is mandatory (CP26/53 in-scope) or voluntary. The only formal cross-regime simplification confirmed to date. See UK SRS Legislation for section-by-section coverage.
Does section 463 protect directors making UK SRS disclosure?
Yes. Section 463 of the Companies Act 200615 provides safe harbour for directors against compensation liability for false or misleading statements in the Strategic Report, Directors' Report, and other reports — directors only liable if they knew of falsity, were reckless, or knew an omission was dishonest concealment. The Government Response to UK SRS Consultation2 confirms section 463 applies automatically when UK SRS disclosure included in the Strategic Report — particularly important for forward-looking disclosures like scenario analysis, anticipated financial effects, and transition plans.
What is the section 172(1) statement?
Section 172 of the Companies Act 20064 imposes the directors' duty to promote the success of the company, with "have regard" to six factors including "the impact of the company's operations on the community and the environment" (section 172(1)(d)). The Section 172(1) statement4 in the Strategic Report explains how directors discharged this duty. UK SRS Governance pillar disclosures1 often overlap with the Section 172(1) statement — both address how the board considers stakeholder and environmental factors.
What are the penalties for non-compliance with UK SRS?
For listed companies in CP26/53 mandatory scope: FCA enforcement under FSMA 2000 — public censure, financial penalties up to 30% of relevant revenue (section 206), listing suspension/cancellation, Senior Managers and Certification Regime accountability. For unlisted companies (when UK SRS adopted voluntarily or under future MCR Strand 28): Companies Act 2006 mechanisms — section 418 director criminal liability (unlimited fine) for non-compliant Directors' Report content4; section 453 civil penalty for late filing (£150-£7,500 schedule); FRC Corporate Reporting Review6 for disclosure quality.
How does UK SRS interact with the Companies Act 2006 Strategic Report?
UK SRS1 disclosure typically sits WITHIN the Strategic Report rather than being a separate document. Section 414A of the Companies Act 20064 establishes the Strategic Report duty; section 414CA4 requires NFSIS within the Strategic Report; section 414CB(1)-(5)5 requires climate-related disclosure within or adjacent to the NFSIS; section 414CB(2A)5 allows UK SRS S2 to satisfy section 414CB(1)-(5). UK SRS S11 application generally satisfies NFSIS environmental and broader sustainability requirements. See UK SRS Reporting Guidance for the Annual Report integration framework.
What is the legal framework for UK SRS?
Four-layer framework: (1) Primary legislation — Companies Act 20064 and Financial Services and Markets Act 2000 (FCA powers); (2) Statutory Instruments — SI 2022/31 (CFD regime), SI 2018/115511 (SECR), SI 2024/1303 (size threshold changes); (3) FCA rules — UK Listing Rules13 and CP26/53; (4) Standards — UK SRS S1 and S21 from DBT, ISSA (UK) 50007 from FRC. Five regulators with distinct roles: DBT, FCA, FRC, Companies House, Environment Agency (for adjacent ESOS). See UK SRS Regulations for detailed coverage.

Adjacent regimes

Six questions covering how UK SRS relates to SECR, ESOS, TCFD, CSRD, and the FCA's SDR for asset managers. For the complete landscape overview, see sustainability reporting as primary reference.

Will UK SRS replace SECR?
No, not in the short term. The two regimes operate alongside each other111. DESNZ has committed to consider how UK SRS and SECR interact "with a view to reducing unnecessary duplication where possible" (Government Response to UK SRS Consultation, February 20262). Separately, DESNZ commissioned an in-depth SECR Post-Implementation Review in January 2025. No supersession timeline has been confirmed. Plan for parallel SECR + UK SRS compliance through at least 2027. See SECR and UK SRS for detailed coverage.
How does UK SRS relate to ESOS?
Different regimes covering different aspects. ESOS12 is a four-yearly mandatory ENERGY AUDIT scheme administered by the Environment Agency under SI 2014/1643 + SI 2023/1182 — Phase 4 compliance deadline 5 December 2027. UK SRS S21 is an annual CLIMATE DISCLOSURE framework under FCA CP26/53 — mandatory from 1 January 2027 for listed companies. Both regimes use the same energy data infrastructure but produce different outputs (Lead Assessor-signed audit + Action Plan for ESOS; Strategic Report disclosure for UK SRS). See ESOS and UK SRS for detailed three-regime view.
How does UK SRS differ from CSRD?
Different materiality concepts and scope. UK SRS1 uses FINANCIAL materiality (single materiality); EU CSRD uses DOUBLE materiality (financial + impact). UK SRS1 applies to listed companies under CP26/53 with potential extension to private companies under MCR Strand 28; CSRD applies to ~50,000 EU and overseas entities with EU operations above thresholds. Both regimes target investor-relevant disclosure but with different scope and content requirements. UK and EU regimes operate independently — UK entities with EU operations may face both.
How does UK SRS differ from TCFD?
UK SRS S21 supersedes TCFD14 for in-scope listed companies under CP26/53 from 1 January 2027. UK SRS S2 builds on the TCFD four-pillar framework but adds: (1) Mandatory Scope 3 disclosure (TCFD didn't require Scope 3); (2) Quantitative scenario analysis (TCFD allowed qualitative); (3) Cross-industry climate metrics (TCFD framework-only); (4) Connectivity with financial statements (TCFD didn't require); (5) Anticipated financial effects (TCFD didn't require). See UK SRS vs TCFD for detailed evolution comparison.
How does UK SRS interact with FCA SDR?
FCA SDR (Sustainability Disclosure Requirements)17 is a separate but related FCA regime for fund labelling and asset manager disclosure (Policy Statement PS23/16, November 2023). SDR applies to asset managers, life insurers, and pension providers in respect of investment products. Under CP26/53, asset managers disclosing under UK SRS S1 and S2 can cross-reference those disclosures in their SDR TCFD entity reports per UK SRS S1 paragraph 651. The two regimes coexist — SDR for product-level disclosure; UK SRS for entity-level sustainability disclosure.
How do UK SRS and ESOS and SECR fit together?
Three regimes with different scope, mandatoriness, and audience. (1) UK SRS S21 — investor-facing annual climate disclosure for listed companies (CP26/5 in-scope) under FCA enforcement3; (2) SECR11 — annual energy and emissions in Directors' Report for large quoted/unquoted/LLP under Companies Act enforcement4; (3) ESOS12 — four-yearly mandatory energy audit for qualifying UK groups under Environment Agency enforcement. Most large UK organisations face all three. Data infrastructure overlap is substantial; outputs and audiences differ. See ESOS and UK SRS for detailed three-regime view.

Assurance and verification

Four questions covering whether assurance is required, ISSA (UK) 5000, limited vs reasonable assurance, and timing.

Is third-party assurance required for UK SRS?
Not mandatory under CP26/53. The FCA has not proposed mandatory third-party assurance for UK SRS in the initial implementation period. However, ISSA (UK) 50007 published by the FRC on 12 November 2025 (effective for periods beginning on or after 15 December 2026) provides the methodology for voluntary assurance engagements. Many UK financial institutions and large corporates plan limited assurance over UK SRS S21 from Year 1 of mandatory application. See UK SRS Assurance for detailed coverage.
What is ISSA (UK) 5000?
ISSA (UK) 50007 is the UK Sustainability Assurance Standard published by the Financial Reporting Council on 12 November 2025, effective for periods beginning on or after 15 December 2026. The standard provides methodology for both LIMITED and REASONABLE assurance engagements over sustainability information. ISSA (UK) 5000 was developed by the IAASB internationally and adapted by the FRC for UK application. It applies to assurance over UK SRS disclosures, SECR content, ESOS-related disclosures, and other voluntary sustainability information.
What is the difference between limited and reasonable assurance?
Limited assurance provides "nothing has come to our attention" conclusion — less evidence gathering, lower cost, faster timeline. Reasonable assurance provides positive "the information is fairly stated" conclusion — substantially more evidence gathering, higher cost, longer timeline. ISSA (UK) 50007 specifies methodology for both levels. Year 1 UK SRS adopters typically obtain limited assurance over Scope 1 and 2 emissions and selected other disclosures; reasonable assurance is more typical for mature sustainability reporting programmes (typically 3-5 years post-initial reporting).
When should assurance start?
Engagement timing depends on assurance level. For limited assurance — engage assurance provider 3-6 months before reporting deadline; data extraction and walkthroughs typically 2-3 months; final fieldwork 1-2 months. For reasonable assurance — engage assurance provider 6-12 months before reporting deadline; substantive testing 4-6 months. Assurance providers operate under independence rules — early engagement helps but the assurance team must remain independent of preparation. See UK SRS Assurance for detailed coverage.

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Last verified 13 May 2026Reviewed by UK SRS Editorial Team
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