FCA PS26/19: What the UK Listing Rules Now Require on Sustainability Disclosure

FCA PS26/19: What the UK Listing Rules Now Require on Sustainability Disclosure

By Usama Imran, ACCA. Sustainability reporting and assurance lead at Spectreco. Published 7 October 2026.

On 30 September 2026 the Financial Conduct Authority (FCA), the United Kingdom’s markets regulator, published Policy Statement PS26/19 and settled a question that had been open since January. It did not make the UK Sustainability Reporting Standards (UK SRS) a hard mandate for listed companies. Instead, in-scope issuers will report against UK SRS on a comply-or-explain basis for accounting periods beginning on or after 1 January 2027, with first reports landing in 2028.

That decision matters because the FCA’s own consultation, CP26/5, had proposed something firmer: mandatory climate disclosure under UK SRS S2 for roughly 515 companies. The final rules softened that to comply-or-explain across every UK SRS requirement.

Spectreco, a sustainability technology and advisory firm with offices in Atlanta, London, Lisbon and Lahore, reads PS26/19 as a change of mechanism, not a reprieve. A comply-or-explain duty is still a Listing Rules obligation. This explainer sets out exactly what the FCA decided, what moved between consultation and final rules, where UK SRS now sits, and what listed companies and investors should do before the first reporting cycle begins.

Source: FCA, PS26/19: Aligning listed issuers’ sustainability disclosures with international standards

Key takeaways

• The FCA’s final rules (PS26/19, 30 September 2026) require in-scope listed companies to report against UK SRS on a comply-or-explain basis for accounting periods beginning on or after 1 January 2027, with first reports in 2028.
• CP26/5 had proposed mandatory UK SRS S2 climate reporting for around 515 companies. The final rules apply comply-or-explain to all UK SRS disclosures, including climate.
• There is a one-year transitional relief for Scope 3 emissions and a two-year relief for the wider UK SRS S1 disclosures, so those obligations phase in from 2028 and 2029.
• The rules replace the 2021 TCFD-aligned listing rules and sit in the amended UK Listing Rules and the ESG Sourcebook.
• UK SRS S1 and S2, published by the Department for Business and Trade on 25 February 2026, remain available for voluntary use for any entity that is not caught by the Listing Rules.

What did the FCA decide in PS26/19?

Direct answer: The FCA adopted a comply-or-explain approach across the full UK SRS framework for listed issuers. The rules apply to accounting periods beginning on or after 1 January 2027, with first reporting in 2028. They replace the existing TCFD-aligned climate disclosure rules.

Comply-or-explain means an issuer either makes the disclosure the standard requires, or states clearly that it has not and why. It is not an option to stay silent.

The rules reach five Listing Rules categories: commercial companies, the transition category, non-equity and non-voting equity shares, international commercial companies with a secondary listing, and depositary receipts. Investment funds, shell companies and debt securities are out of scope. Two transitional reliefs ease the start: non-disclosure of Scope 3 emissions under UK SRS S2 for one year, and non-disclosure of the non-climate UK SRS S1 matters for two years, which the FCA frames as climate-first reporting.

Sources: FCA, PS26/19 policy statement (PDF), ESG Today

What changed between CP26/5 and the final rules?

The headline change is the move from a mandate to comply-or-explain. CP26/5, published on 30 January 2026, proposed mandatory UK SRS S2 climate disclosure for the main listing categories, with a lighter touch for secondary listings and depositary receipts. PS26/19 replaced that split with a single comply-or-explain regime for all five categories.

The FCA’s reasoning was proportionality. Mandatory application, it concluded, would weigh on smaller and earlier-stage issuers and produce limited value where climate is not financially material to the business.

In the FCA’s words, the final approach “will support the consistent disclosure of financially material, decision-useful information while retaining flexibility for issuers, particularly those at an earlier stage of their lifecycle,” per Alicia Kedzierski, the FCA’s Head of Sustainable Finance.

One practical effect: firms already subject to TCFD entity reporting under the ESG Sourcebook can cross-refer to their UK SRS disclosures and avoid duplicating the work.

Sources: FCA, PS26/19 policy statement (PDF), ESG Today

Is UK SRS mandatory for listed companies now?

Direct answer: No. Under PS26/19, UK SRS is required on a comply-or-explain basis, not as an absolute mandate. In-scope listed companies must either disclose against UK SRS S1 and S2 or explain why they have not, for accounting periods beginning on or after 1 January 2027.

Comply or explain is not a loophole

A thin explanation is a disclosure in its own right, and investors read it first. Comply-or-explain is a transition mechanism designed to let issuers build capability in order, not a permanent opt-out. Proxy advisers and lenders will treat a weak explanation as a signal about governance long before the FCA raises it.

Voluntary use and early adoption

UK SRS S1 and S2 were published by the Department for Business and Trade on 25 February 2026 as the UK’s endorsement of the ISSB standards IFRS S1 and IFRS S2. They are available for voluntary use now. Companies with an accounting period beginning before 1 January 2027 can keep their current reporting or adopt UK SRS early, and early adopters can use the same transitional reliefs.

Source: Linklaters, UK government publishes final versions of UK SRS

What should listed companies and investors do now?

For issuers, the comply-or-explain window is a build runway, not a pause. The gap between a TCFD statement and a full UK SRS disclosure is a data and governance problem first. Three moves are worth starting before the 2027 cycle opens.

1. Run a gap analysis against your current TCFD disclosure. Map each element of your existing climate statement to UK SRS S1 and S2, and flag where you have narrative but no quantification, scenario analysis or financial-statement connectivity.
2. Fix Scope 3 data while the relief runs. The one-year Scope 3 window closes for periods beginning on or after 1 January 2028. Start supplier data collection now and align it with the GHG Protocol so the numbers survive assurance later.
3. Decide what you will explain, and document why. Where you will not yet comply, write the explanation and the timeline to close the gap, rather than leaving it to the reporting team in the final weeks.

Spectreco’s full readiness plan sits in its companion guide, UK Sustainability Reporting Standards: what UK-listed companies must know from 2027. Financial firms should also separate their issuer duty from their fund-level obligations, as set out in UK SRS for asset managers.

For investors, the signal to watch is the quality of the explanation, not just the presence of a disclosure. A managed Virtual Sustainability Office can carry the reporting load through the transition without permanent headcount.

What PS26/19 means for CSRD dual reporters

Direct answer: For a group with both a UK listing and EU operations, PS26/19 does not reduce the EU workload. The core difference is materiality. UK SRS uses single, financial materiality: how sustainability affects the company. The EU’s Corporate Sustainability Reporting Directive (CSRD) uses double materiality, which adds the company’s impact on people and the environment.

A strong UK SRS report does not, on its own, satisfy CSRD, and a CSRD report does not satisfy UK SRS. The two usually attach to different entities in the same group: a UK-listed parent reports under UK SRS by virtue of its listing, while a qualifying EU subsidiary reports under CSRD.

The efficient path is one climate core built to the stricter standard, then calibrated per regime, rather than two parallel programmes. Spectreco’s view on why the EU’s 2026 Omnibus cuts did not make EU reporting optional is set out in the EU Omnibus and why ESG reporting is still required.

Source: Nexio Projects, UK SRS vs CSRD vs IFRS S1/S2: building an interoperable reporting system

Frequently Asked Questions

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Map your UK SRS obligations with Spectreco

PS26/19 turns an open policy debate into a reporting timetable. The companies that file a clean UK SRS report in 2028 are the ones mapping their gap now, while the standard is still voluntary and the comply-or-explain windows are open.

Spectreco’s London-based advisory team runs a UK SRS compliance and reporting gap assessment that maps your current TCFD disclosure against UK SRS S1 and S2, flags the Scope 3 and connectivity gaps you will fail assurance on, and sets a plan against the 2027, 2028 and 2029 milestones. Book your UK SRS readiness review with Spectreco and walk into the first reporting cycle knowing exactly what to file, and what to explain.