UK SRS vs CSRD — two frameworks, one foundation

What each framework is

UK SRS (UK Sustainability Reporting Standards) consists of two standards published by the Department for Business and Trade in February 2026: S1 covering general sustainability-related financial disclosures and S2 covering climate-related disclosures. They are direct UK endorsements of the ISSB's IFRS S1 and IFRS S2, with modifications for UK legal context.

CSRD (Corporate Sustainability Reporting Directive) is the EU legislative framework under Directive 2022/2464/EU, mandating compliance with the 12 European Sustainability Reporting Standards (ESRS) developed by EFRAG and adopted by the European Commission in delegated regulation 2023/2772.

ESRS covers environmental, social, and governance topics across all sustainability domains — going considerably further than the ISSB baseline.

Both frameworks emerged from the same international convergence effort and share ISSB climate foundations.

The differences reflect deliberate policy choices: the UK government chose to adopt the narrower ISSB investor-focused baseline; the EU chose a broader multi-stakeholder approach requiring double materiality.

Shared ISSB foundation

Both UK SRS and CSRD are built on the ISSB's sustainability disclosure architecture. IFRS S1

and IFRS S2, published by the ISSB in June 2023, established the global baseline for sustainability-related financial disclosures.

The UK endorsed this baseline directly as UK SRS S1 and UK SRS S2.

The EU's ESRS E1 climate standard was developed with explicit reference to IFRS S2, creating substantial overlap on climate topics.

For companies reporting under both frameworks, the climate disclosure layer (UK SRS S2 and ESRS E1) is the area of greatest overlap.

Data infrastructure built for UK SRS S2 Scope 1, 2, and 3 emissions disclosure will serve ESRS E1 requirements — though ESRS E1 has additional requirements beyond the ISSB baseline, including transition plan templates and specific biodiversity-linked disclosures.

The materiality divide

The most fundamental difference between UK SRS and CSRD is the materiality approach.

This determines which disclosures a company must make and shapes the entire reporting exercise.

Financial materiality (UK SRS)

UK SRS follows the ISSB's financial materiality approach.

Under UK SRS S1 paragraph 17, sustainability-related information is material if omitting, misstating, or obscuring it could reasonably be expected to influence the decisions of primary users of financial reports — investors and creditors.

This is equivalent to the financial materiality concept used in IFRS accounting standards.

Companies assess which sustainability matters are financially material to their business and disclose accordingly.

Double materiality (CSRD)

CSRD requires a double materiality assessment under Directive 2022/2464/EU Article 19a.

Companies must assess both (1) how sustainability matters affect the company's financial performance, position, and cash flows (financial materiality, also called "outside-in"), and (2) how the company's activities impact people and the environment (impact materiality, also called "inside-out").

Information is material for CSRD purposes if it is material under either lens — or both.

The practical effect: a company's Scope 3 value chain emissions may be immaterial from a financial perspective but material from an impact perspective under CSRD's double materiality lens.

Under UK SRS's financial materiality approach, if those emissions have no reasonably foreseeable financial effect on the company, disclosure is not required.

CSRD would require disclosure of the impact regardless.

Topic coverage differences

UK SRS covers two topics: general sustainability-related financial information (UK SRS S1) and climate (UK SRS S2).

This is a deliberate choice to adopt only the ISSB baseline, leaving other sustainability topics — biodiversity, social, governance — out of the mandatory UK SRS framework.

CSRD mandates 12 ESRS standards covering all sustainability topics.

The full ESRS landscape includes cross-cutting standards (ESRS 1 general requirements, ESRS 2 general disclosures), environmental standards (E1 climate, E2 pollution, E3 water, E4 biodiversity, E5 circular economy), social standards (S1 own workforce, S2 value chain workers, S3 affected communities, S4 consumers/end-users), and governance (G1 business conduct).

• Biodiversity and ecosystems: not in UK SRS; mandatory under ESRS E4
• Own workforce social topics: not in UK SRS; mandatory under ESRS S1
• Value chain social impacts: not in UK SRS; mandatory under ESRS S2
• Pollution: not in UK SRS; mandatory under ESRS E2
• Water and marine resources: not in UK SRS; mandatory under ESRS E3
• Business conduct/governance: not in UK SRS; mandatory under ESRS G1

For companies already reporting under CSRD, this means their ESRS-compliant reports will contain considerably more sustainability information than UK SRS requires.

The CSRD report exceeds UK SRS requirements at the climate level (ESRS E1 has more requirements than UK SRS S2 in some areas) and adds substantial additional disclosure across all other topics.

Scope and thresholds

UK SRS mandatory application is being introduced via FCA CP26/5 for companies listed in specific UKLR categories.

The initial mandatory scope covers UKLR categories 6, 14, 15, 16, and 22 — primarily premium-listed and standard-listed commercial companies — from reporting years beginning on or after 1 January 2027.

The government's Modernising Corporate Reporting (MCR) programme is expected to extend UK SRS to large private companies through a separate consultation (MCR Strand 2).

CSRD scope has been significantly narrowed by Directive (EU) 2026/470 ("Omnibus I"), published in the Official Journal on 26 February 2026 and in force from 18 March 2026.

Under the revised thresholds, CSRD applies to EU companies with more than 1,000 employees AND at least €450 million net annual turnover — up from the original 2022 entry point of large undertakings from 250 employees.

For third-country companies (including UK-headquartered groups), the Article 40a route applies where EU net turnover exceeds €450 million in each of the last two consecutive financial years and the group has a large EU subsidiary or an EU branch with turnover above €200 million, with group-level reporting from financial year 2028.

See our dedicated CSRD for UK companies guide for the full scope test.

Mandatory timelines

UK SRS: FCA CP26/5 proposes mandatory application for UKLR categories 6, 14, 15, 16, and 22 for reporting years beginning on or after 1 January 2027.

The consultation closed in mid-2026; final FCA rules are expected to confirm this timeline.

Voluntary application of UK SRS S1 and S2 is available from the publication date of February 2026.

CSRD: under the original 2022 directive, the first wave of large listed EU companies was required to report for financial year 2024.

Post-Omnibus, the CSRD timeline for many companies has shifted — the revised scope requiring more than 1,000 employees AND at least €450 million turnover narrows mandatory application, and companies outside the new thresholds are not required to report for financial years starting on or after 1 January 2027.

UK-headquartered groups instead face the Article 40a third-country route, with group-level reporting from financial year 2028.

Companies that were preparing for the earlier, broader CSRD scope should reassess their mandatory status under the revised thresholds.

The practical implication: UK-listed companies that had been preparing for CSRD compliance (expecting large listed company scope) should confirm whether the revised Omnibus thresholds still apply to them before finalising their reporting approach.

Cross-border companies

UK companies with EU subsidiaries, EU-listed securities, or significant EU revenues may face obligations under both frameworks.

EU-headquartered companies with UK listings may similarly face dual requirements.

Several scenarios are worth examining:

• UK company with UKLR Category 6 listing AND EU subsidiary above CSRD thresholds: likely dual obligations under both UK SRS (via CP26/5) and CSRD
• EU company with UK listing in UKLR Category 6: UK SRS mandatory from January 2027; CSRD mandatory under EU Omnibus-revised thresholds (if met)
• UK company with EU revenues >€450m but no EU listing: the Article 40a third-country route may apply if it also has a large EU subsidiary or an EU branch above €200m turnover; UK SRS applies if UK-listed in relevant UKLR categories
• Large UK private company: not yet in UK SRS mandatory scope (pending MCR Strand 2); may be in CSRD scope if EU thresholds met

Where dual compliance is required, companies can build shared data infrastructure — particularly for climate and general sustainability topics where UK SRS S2 and ESRS E1 overlap.

However, the double materiality assessment required for CSRD is a distinct exercise from the financial materiality assessment under UK SRS S1 paragraph 17 and cannot be collapsed into a single process without risk of gaps in either framework.

Side-by-side comparison

The table below summarises the key differences between UK SRS and CSRD/ESRS across ten dimensions relevant to compliance planning.

Frequently asked questions