Key UK SRS dates and milestones
The proposed-mandatory dates depend on the FCA Policy Statement
The dates shown above for the Effect track are proposed, not yet legally binding.
They depend on the FCA's autumn 2026 Policy Statement on CP26/51.
UK SRS itself contains no effective date clauses.
Those come from the FCA for SRS compliance companies1, or from future Government consultation for private companies3.
For the complete regulatory framework underlying these timelines, see our UK SRS regulations guide.
The standards published 25 February 20262 are available for voluntary adoption immediately.
For the complete publication timeline and context, see UK SRS 2026 publication details.
Complete UK SRS implementation timeline
Comprehensive timeline from publication through voluntary adoption to proposed mandatory compliance
From consultation to compliance
The path from DBT standards to mandatory reporting.
Each milestone links to its primary source.
What happens when CP26/5 is finalised
The FCA's CP26/5 consultation1 closed on 20 March 2026.
The Policy Statement, expected autumn 2026, will confirm or modify the proposed rules before they come into force on 1 January 20271.
The proposed 1 January 2027 date would apply to accounting periods beginning on or after that date — not to reports published after that date1.
This means that a company with a December year-end first reports for the period 1 January 2027 to 31 December 20272, with that report published in spring 2028.
When the first proposed-mandatory reports appear
| Financial year-end | First proposed-mandatory period | First report published (typical) |
|---|---|---|
| 31 December | 1 Jan 2027 to 31 Dec 2027 | Spring 2028 (March–April) |
| 31 March | 1 Apr 2027 to 31 Mar 2028 | Summer 2028 (June–August) |
| 30 June | 1 Jul 2027 to 30 Jun 2028 | Autumn 2028 |
| 30 September | 1 Oct 2027 to 30 Sep 2028 | Winter 2028–29 |
For a typical FTSE 350 company with December year-end, this gives an 18-month window from publication (February 2026)2 to first report.
The FCA's CP26/5 cost-benefit analysis found around 600 listed companies affected, of which 515 (in the commercial companies, non-equity shares and non-voting equity shares, or transition categories) are required to comply, and 89 (secondary listing and depositary receipts) face a lighter-touch disclosure only1 — see who must comply with UK SRS for the entity-level test, and the UK SRS deadline page for dates by entity type.
Most of that window goes to data systems, materiality assessment2, scenario analysis, and assurance preparation under ISSA (UK) 50004.
The Scope 3 transitional treatment
FCA CP26/51 proposes who must comply can omit Scope 3 emissions in their first year of mandatory reporting under the S2 climate standard (paragraphs 3.9 and 8.6 of CP26/51).
From accounting periods beginning on or after 1 January 2028, Scope 3 reporting moves to comply-or-explain across all 15 GHG Protocol7 categories where material.
The GHG Protocol Corporate Value Chain (Scope 3) Standard7 defines the 15 categories that must be assessed.
This recognises the data challenges in value chain emissions reporting while maintaining disclosure expectations1.
The UK SRS S2 standard2 mirrors this phasing from its parent IFRS S26.
S1 and S2 Integration Timeline
S1 Foundation Elements (2027)
Materiality definitions, value chain scope, and connected information (financial-statement links) apply immediately with S2 because S2 cannot operate without them
S2 Climate Focus (2027)
Complete four-pillar climate reporting including governance, strategy, risk management, and metrics & targets
Scope 3 Enhancement (2028)
Value chain emissions across 15 GHG Protocol categories move from relief to comply-or-explain
S1 Broader Sustainability (2029)
General sustainability disclosures beyond climate move to comply-or-explain for listed companies
UK SRS S1 timeline
The conceptual foundation elements of S1 standard2 — definitions of materiality, scope of value chain, connected information (¶¶21–24) — apply from January 2027 alongside UK SRS S2 because S2 requirements cannot be applied without them.
UK SRS S1 was published on 25 February 2026 alongside S22.
The broader general sustainability disclosures move to comply-or-explain from January 2029 under FCA CP26/51 (paragraph 3.11).
The Government response to consultation confirmed this phased approach3.
This creates a logical implementation timeline sequence: climate first (SRS S2), then broader sustainability (SRS S1)2, with foundational concepts applying throughout.
The UK SRS standards are grounded in the Companies Act 20065 framework for strategic report disclosures.
What each phase actually asks companies to disclose is summarised in UK SRS requirements; every page in this cluster is indexed from the UK SRS hub.
How the UK’s proposed timeline compares internationally
Close to 40 jurisdictions have adopted or are moving toward ISSB Standards1.
Three of the UK’s closest comparators have already made climate disclosure mandatory law; a fourth has aligned standards that remain voluntary.
The UK’s S2 date is still a proposal in a way none of the other three are.
| Jurisdiction | Standard | Status | Detail |
|---|---|---|---|
| Australia | AASB S2 | Mandatory from 1 Jan 2025 | Group 1 (largest) entities already reporting; Group 2 commenced 1 July 2026 and Group 3 follows on 1 July 2027. Already binding law, not a proposal. |
| Japan | SSBJ Standards | Mandatory from FY March 2027 | Voluntary early application from FY March 2026; mandatory for the largest Tokyo Prime Market issuers (¥3tn+ market cap) from FY March 2027, phasing down by size to FY March 2029. |
| Singapore | SGX climate disclosure rules | Mandatory from FY 2025 | Scope 1–2 already mandatory for all SGX-listed issuers from FY2025; Scope 3 from FY2026 for the largest (STI-constituent or S$1bn+ market cap) issuers. |
| Canada | CSDS 1 and CSDS 2 | Still voluntary | Published Dec 2024, aligned with ISSB — not mandatory unless and until a securities regulator adopts them. Government signalled intent to mandate disclosure for large companies in Oct 2024; no effective date has been set. |
The UK’s position is closer to Canada’s than to Australia, Japan or Singapore’s: a published standard with no legally binding application date yet.
The difference is that CP26/5 has already specified the date it proposes — 1 January 20271 — where Canada has not yet proposed one at all.
How investors and industry bodies responded to the proposed dates
CP26/5 attracted formal responses from institutional investors, asset managers and professional bodies.
Positions differed on how much relief the comply-or-explain treatment for Scope 3 and S1 should carry — a live disagreement, not a settled question.
The PRI welcomed the FCA’s proposal9, saying the UK’s near-full convergence with ISSB Standards “will help to provide investors with access to decision-useful sustainability information.” Norges Bank Investment Management10
took a more assertive position, arguing “UK SRS S1 should also have a clear mandatory reporting timeline.
Non-climate sustainability information is equally capable of being financially material… An open-ended ‘comply or explain’ regime provides insufficient certainty for preparers or investors.”
The Investment Association, whose 250 members manage £10 trillion for savers and institutions, backed the S2 timetable and the Scope 3 one-year relief, but pressed the FCA to set a clear mandatory date for S1 rather than leaving it open-ended.
The Institute and Faculty of Actuaries and ICAEW, by contrast, supported the comply-or-explain treatment largely as proposed — ICAEW’s one substantive ask was timing relief for restating Scope 3 comparative figures, not a different regime.
The FCA’s own rationale for comply-or-explain is that broader sustainability reporting is new for many companies, and that Scope 3 measurement challenges justify a one-year deferral1.
Timeline Implementation Checklist
Voluntary adoption phase (Now - 2027)
Begin voluntary UK SRS S1/S2 application to test systems and build capability before mandatory requirements
Policy Statement monitoring (Autumn 2026)
Track FCA Policy Statement for final mandatory dates, scope, and any modifications to CP26/5 proposals
S2 proposed-mandatory preparation (2027)
Complete climate reporting implementation including governance, strategy, risk management, and metrics
Scope 3 readiness (2028)
Prepare for comply-or-explain Scope 3 disclosure across material GHG Protocol categories
S1 broader sustainability (2029)
Implement general sustainability disclosures beyond climate on comply-or-explain basis
Assurance engagement
Plan ISSA (UK) 5000 assurance provider engagement and trial assurance processes
Frequently asked questions
When does UK SRS become mandatory?
UK SRS S2 is proposed mandatory for accounting periods beginning on or after 1 January 2027, under FCA CP26/51 paragraph 3.7.
The FCA's final Policy Statement is expected autumn 20261 (paragraph 1.11).
UK SRS itself contains no effective date clauses — the standards were published by DBT on 25 February 20262.
Is UK SRS available now?
Yes, for voluntary use.
The standards were published by DBT on 25 February 20262 and are available immediately for voluntary adoption.
Proposed mandatory application for listed companies is subject to the FCA's CP26/5 proposals1.
The Government response to the consultation confirmed the standards are suitable for voluntary adoption from the date of publication3.
What is the Scope 3 carve-out?
FCA CP26/51 (paragraphs 3.9 and 8.6) proposes that companies can omit Scope 3 emissions in the first year of proposed mandatory reporting.
From accounting periods beginning 1 January 2028, Scope 3 moves to comply-or-explain across all 15 GHG Protocol7 categories where material.
The GHG Protocol defines the 15 Scope 3 categories7 that must be assessed under this requirement.
When are the first proposed mandatory reports published?
For companies with December year-ends — typical for FTSE 350 — the first proposed mandatory accounting period begins 1 January 2027 and the first report typically publishes in spring 20281.
Year-ends in March, June, or September produce later first reports through 2028 and into 2029.
The FCA's CP26/5 Annex 2 cost-benefit analysis1 found around 600 listed companies affected: 515 required to comply, and 89 (secondary listing and depositary receipts) facing a lighter-touch disclosure only.
When does UK SRS S1 become mandatory?
Under CP26/51 (paragraph 3.11), UK SRS S12 (broader sustainability) moves to comply-or-explain for accounting periods beginning 1 January 2029.
The conceptual foundation elements of S1 — materiality definitions, value-chain scope, connected information (¶¶21–24) — apply from January 2027 alongside S22.
How does ISSA (UK) 5000 fit the timeline?
The FRC published ISSA (UK) 5000, the UK sustainability assurance standard, on 12 November 20254.
It is effective for assurance engagements on sustainability information reported for periods beginning on or after 15 December 2026, or as at a specific date on or after that day4 — earlier application is permitted, so it can already be applied voluntarily, ahead of UK SRS S2's proposed mandatory disclosures.
