What is UK SRS? S1 and S2 explained
The UK Sustainability Reporting Standards are two standards, not one. UK SRS S1 covers every material sustainability topic except climate; UK SRS S2 covers climate. Both were published by the Department for Business and Trade on 25 February 2026 and are voluntary today — S2 proposed mandatory from 1 January 2027, S1 on comply-or-explain from 1 January 2029.
Where the framework comes from
UK SRS did not appear from nowhere. It is the third link in a chain running from TCFD in 2017, through the ISSB's global baseline, to the UK's endorsed standards. Select a step.
Two standards.
One framework.
UK SRS S1 and S2, compared
The same four pillars, the same materiality basis, different subjects and dates two years apart. Read one standard at a time, or set them side by side.
Four pillars, two readings
Both standards use the same TCFD four-pillar structure. S1 applies it to every material sustainability topic; S2 applies it to climate. Expand a pillar to see both readings.
From consultation to comply-or-explain
Eight dates run from the FCA's consultation to S1's comply-or-explain start. Everything after the autumn 2026 Policy Statement is proposal, not law.
Who must comply
Voluntary for everyone today. Roughly 515 listed companies are proposed in scope from 2027; large private companies remain under review. Expand any tier.
Six UK amendments to the ISSB baseline
The UK adopted IFRS S1 and S2 and changed them in exactly six places. Select any amendment to read what changed.
The implementation sequence
Five stages from confirming applicability to engaging an assurance practitioner. Tick them off as you go — the state is yours, nothing is sent anywhere.
Enough depth.
Now the reference.
The UK SRS framework — key facts
- Full name
- UK Sustainability Reporting Standards framework (UK SRS S1 + UK SRS S2)
- Publisher
- Department for Business and Trade (DBT)
- Published
- 25 February 2026
- Baseline
- IFRS S1 and IFRS S2 (ISSB, June 2023)
- Amendments
- 6 UK-specific
- Pillars
- 4 — governance, strategy, risk management, metrics & targets
- Status now
- Voluntary for any UK entity
- S2 mandatory
- 1 January 2027 (proposed, in-scope listed issuers)
- Scope 3
- Comply-or-explain from 1 January 2028
- S1 mandatory
- 1 January 2029 (comply-or-explain)
- Private companies
- Under review via the MCR programme
- Replaces
- TCFD-aligned Listing Rules
Frequently asked questions
UK SRS S1 provides general requirements for disclosure of sustainability-related financial information covering all material sustainability topics except climate (biodiversity, water, workforce, supply chain, human rights, governance, resource use). It follows single (financial/enterprise-value) materiality on the ISSB/IFRS S1 basis and is proposed for mandatory comply-or-explain application from 1 January 2029.
UK SRS S2 covers climate-related disclosures using the four-pillar TCFD architecture (Governance, Strategy, Risk Management, Metrics & Targets). It's proposed for mandatory application to UK-listed companies from 1 January 2027, with Scope 3 emissions on comply-or-explain from 1 January 2028.
UK SRS S1 provides the architectural foundation (materiality, connectivity, value chain principles) that UK SRS S2 climate disclosures rely on. While UK SRS S2 is proposed to apply first (1 January 2027 under FCA CP26/5, subject to the autumn 2026 Policy Statement), UK SRS S1 concepts are essential for proper UK SRS S2 implementation. Companies cannot apply UK SRS S2 in isolation without understanding UK SRS S1 principles.
Under FCA CP26/5 proposals, UK SRS S2 becomes mandatory for in-scope listed companies from 1 January 2027, with Scope 3 emissions on comply-or-explain from 1 January 2028. UK SRS S1 follows on comply-or-explain from 1 January 2029. CP26/5 closed for consultation on 20 March 2026; the FCA Policy Statement confirming final rules is expected autumn 2026.
Approximately 515 UK-incorporated LSE-listed companies under UKLR 6, 14, 15, 16, and 22 are proposed for mandatory UK SRS S2 from 2027, followed by UK SRS S1 from 2029. Private companies remain under review via the Modernising Corporate Reporting (MCR) programme with DBT consultation expected later in 2026. Any UK entity can voluntarily adopt UK SRS S1 and S2 now.
The UK SRS framework consists of UK SRS S1 (general sustainability requirements) and UK SRS S2 (climate disclosures), published by the Department for Business and Trade on 25 February 2026. The framework is based on IFRS S1 and S2 with six UK-specific amendments. UK SRS S1 and UK SRS S2 work together to provide comprehensive sustainability reporting for UK companies.
The UK made six key amendments to IFRS S1 for UK SRS S1: (1) UK effective dates replace ISSB references, (2) first-year transitional relief removed, (3) climate-first relief reworked to match UK phasing, (4) SASB 'shall' softened to 'may', (5) GICS classification requirement removed, and (6) connectivity to financial statements clarified for UK context. These amendments also impact UK SRS S2 implementation.
UK SRS S2 retains the four-pillar TCFD architecture but with enhanced disclosure requirements. The TCFD framework was formally disbanded in October 2023 and succeeded by ISSB standards which UK SRS adopts. UK SRS provides more prescriptive requirements than previous TCFD-aligned Listing Rules.
No mandatory assurance is proposed in the initial phase. Under FCA CP26/5, in-scope companies must disclose whether they have obtained third-party assurance (disclose-or-explain). UK practitioners use ISSA (UK) 5000 standards. The FRC maintains an interim Sustainability Assurance Register.
Yes, UK SRS S1 and S2 are available now for voluntary early adoption by any UK entity with all-or-nothing compliance required (no partial adoption). Early adoption requires a full statement of compliance with the chosen standard(s). Many companies are using the voluntary period for readiness testing.
UK SRS follows single materiality (investor-focused) while EU CSRD uses double materiality (investor + impact). UK SRS is based on IFRS S1/S2 with UK amendments, while ESRS uses a broader EU-specific framework. Both cover climate and broader sustainability topics but with different scopes and requirements.
The FRC provides guidance and maintains a practitioner assurance register. Professional bodies including ICAEW, ACCA, and CIMA offer training and resources. The government published detailed implementation guidance alongside the final standards.
Go deeper on either standard
UK SRS S1 in full
The general standard — four-pillar spine, six amendments and the materiality test.
StandardUK SRS S2 in full
Climate disclosures, Scope 1–3, scenario analysis and transition plans.
TimelineThe full implementation timeline
Every date from CP26/5 through S2 in 2027 to S1 in 2029.
ScopeWho is in scope
Which entities the FCA's proposals actually reach, and which remain under review.
RoadmapUK SRS compliance guide
A sequenced plan for voluntary adoption and mandatory readiness.
ReadinessReadiness assessment
A structured gap analysis across the four pillars.
ComparisonUK SRS vs EU CSRD
Single materiality against double; two standards against twelve.
TransitionTCFD to UK SRS
What changes for existing TCFD-aligned reporters.
AssuranceSustainability assurance
Disclose-or-explain, ISSA (UK) 5000 and the FRC's interim register.
Primary sources
S2 lands first. S1 holds it up.
Climate is mandatory two years before the general standard — but S2 cannot be applied in substance without S1's materiality, connectivity and value-chain concepts already in place.