Reference · updated 17 August 2026
Sustainability reporting — what it is, who reports, and which frameworks apply
Sustainability reporting is the disclosure of environmental, social and governance information about an organisation — and in the United Kingdom it is not one regime but six, only three of which are law.
This page separates what you must do from what you may do, names the instrument behind each, and works out which of them apply to you.
What sustainability reporting is
Sustainability reporting is the disclosure of environmental, social and governance information about an organisation’s activities, performance and impacts — published on a regular cycle, usually annually, usually alongside the financial statements.
The phrase is used loosely, and the looseness is expensive: four different obligations get called “sustainability reporting” in the same meeting, and only one of them is usually the one being asked about. The next section separates them.
What it is not — four words that are not interchangeable
CSR reporting, ESG reporting, a carbon footprint and sustainability reporting are four different things. Search traffic treats them as synonyms. Regulators do not.
The distinction matters most when someone asks whether you “have to do sustainability reporting”. Under SI 2018/1155 a large UK company almost certainly does. Under CSR, nobody does. Both answers are correct to different questions.
What is actually in a sustainability report
Every standard descended from the TCFD’s 2017 recommendations uses the same four pillars. Once you can see them, most reports stop looking different from each other.
UK SRS S1 and S2 keep those four pillars, as do IFRS S1 and IFRS S2 before them, and the ESRS as well. What differs between frameworks is scope, materiality and how much of the fourth pillar is prescribed — not the shape.
The landscape, in one picture
Six regimes touch a UK organisation. They were made at different times, by different bodies, for different readers, and no one of them was designed to fit the others.
The bars are scale, not importance. What they show is that the regimes with the largest reach are the oldest and least discussed, and the ones generating the most commentary reach the fewest organisations — and in two cases are not yet obligations at all.
Almost nothing you have just read is currently law in the United Kingdom.
Three of the six are. The rest are published, consulted on, or announced. Below the line, which is which — and what that means for what you do this year.
Which of these is actually law today
The single most common error in UK sustainability reporting content is describing a proposal as a requirement. This is the state of each regime as at 17 August 2026.
The FCA’s own Next steps note on CP26/5 says it “aim[s] to publish a Policy Statement in autumn 2026”. Until it does, no listed company is required to report against UK SRS, and any page telling you otherwise is describing the future in the present tense.
Are you in scope — and of what
Of the pages that rank for this subject, none computes anything. Five questions settle it for almost every UK organisation.
The router uses the thresholds as they stand today: SI 2018/1155 for SECR, the Environment Agency’s Phase 4 guidance for ESOS, SI 2022/31 for the climate-related financial disclosure duty, CP26/5 paragraph 3.4 for the proposed UK SRS population, and Directive (EU) 2026/470 for CSRD. Where a regime is a proposal it says so rather than returning a yes.
SECR — the one that actually catches you
Streamlined Energy and Carbon Reporting has been mandatory since financial years beginning on or after 1 April 2019, and it reaches roughly forty times as many organisations as everything the FCA has proposed.
Depth on the thresholds, the group rules and the exemptions is on the SECR thresholds page, which computes them, and the SECR exemptions page.
The uplift trap — medium-sized for your accounts, still a SECR reporter
In April 2025 the Companies Act size limits rose. SECR’s did not. Nobody writing about this has noticed, and the gap between the two tests is a real population of real companies.
SI 2024/1303 raised the medium/large boundary for financial years beginning on or after 6 April 2025. But the SECR thresholds are written into Schedule 7 of the 2008 Accounts Regulations in their own right, and were not uprated with them — which GOV.UK’s own current SECR guidance confirms by still stating £36 million and £18 million after the uplift took effect.
A company reclassified as medium-sized for its accounts can still be a SECR reporter. The two tests no longer describe the same companies.
The consequence, stated plainly
How many companies this actually reaches
The figure in circulation is 11,900. It comes from a 2018 impact assessment and it is obsolete. The measured number is 19,900.
The DESNZ post-implementation review of 26 May 2026 is also the answer to the claim that UK SRS is about to replace SECR. Its recommendation is to “retain SECR requirements with amendments”, and it warns that removing SECR “would risk reversing gains in transparency and accountability”. The Regulatory Policy Committee’s opinion records the departmental recommendation as amend, not remove.
ESOS — the nearest hard deadline, and the one nobody writes about
Phase 4 has a qualification date four months from now and a compliance deadline in December 2027. Of the pages ranking for sustainability reporting, not one carries it.
The qualification test is asymmetric and often misread: 250 or more employees qualifies you on its own, or an annual turnover over £44 million and a balance sheet total over £38 million together. Group aggregation applies. The ESOS thresholds page works it through, and the action plan page covers what follows.
What changed six weeks ago — SI 2026/701
On 22 July 2026 two routes to ESOS compliance were removed. GOV.UK’s own ESOS guidance page has not caught up, and no page ranking for this subject mentions it at all.
This is the clearest current example of why a page like this needs a date on it. The GOV.UK ESOS guidance still describes the regime as the 2014 Regulations as amended by the 2023 Regulations. For Phase 4 planning, read the 2026 instrument directly.
Climate-related financial disclosure — section 414CB
The Companies Act duty that most people call “TCFD reporting”. It is in force, unamended, and it is not the thing the FCA has proposed to delete.
What CP26/5 would delete is the FCA’s TCFD-aligned Listing Rules — a different obligation on a different population, made by a different body. The TCFD requirements page separates the two, and the UK SRS versus TCFD comparison covers what changes.
What you do not have to report twice — and what you do
There is exactly one confirmed simplification across the UK framework, and one widely repeated claim that is wrong.
UK SRS S1 and S2 — published, and voluntary
The Department for Business and Trade published both standards on 25 February 2026. They are available for voluntary use by any entity that chooses to apply them.
The six amendments proposed in the June 2025 consultation, and how the two standards interlock, are covered on the UK SRS explainer, with the dates on the UK SRS timeline and the two standards individually on the compliance guide. The underlying IFRS S1 and IFRS S2 texts are free to read.
What the FCA has proposed — and has not yet made
CP26/5 opened on 30 January 2026 and closed on 20 March 2026. As at today, no Policy Statement has been published and no rule has been made.
The distinction that most coverage misses: of the five categories named at paragraph 3.4, UKLR 6, 16 and 22 would report against UK SRS; UKLR 14 and 15 would publish a transparency statement instead. Climate disclosure under S2 would be mandatory except Scope 3, which is comply-or-explain; the wider S1 requirements comply-or-explain after two years’ relief. Assurance is not mandated — what is proposed is a statement of whether assurance was obtained.
What you actually do, and in what order
The four regimes are usually presented side by side, as though you pick one. They are sequential: each one’s output is the next one’s input.
This is deliberately not scored. There is no maturity rating here and no percentage — the question “what do I do first” has an answer that depends on your year-end and your scope, and a number would only disguise that. What the diorama shows is which data each regime consumes and which it produces.
Single and double materiality — the choice that decides everything else
It is one methodological decision, and it determines what goes in the report, who the report is for, and how long it takes to produce.
Single (financial) materiality
How sustainability matters affect the company. Used by UK SRS, IFRS S1 and S2, SASB and the s.414CB duty. The reader is an investor.
Double materiality
That, and the company’s effects on people and the environment. Used by CSRD and the ESRS. The reader is anyone affected. Unchanged by the Omnibus.
The practical consequence is workload. A single-materiality assessment asks which sustainability matters could move your numbers. A double-materiality assessment asks that and then repeats the exercise outward across the value chain. A UK group with EU operations may have to do both — see the UK SRS versus CSRD comparison.
CSRD after the Omnibus — most of it went away
Directive (EU) 2026/470 entered into force on 18 March 2026 and cut the expected population by roughly nine in ten. Wikipedia and most UK “cheat sheets” still publish the superseded thresholds.
Both limbs are cumulative — over 1,000 employees and net turnover over €450 million — and the first financial years are those starting on or after 1 January 2027, with first reports in 2028. Listed SMEs are out. Sector-specific ESRS were deleted outright, replaced by non-binding guidance, and a value-chain cap protects undertakings below 1,000 employees from unlimited data requests. Double materiality is unchanged. The full picture is on the ESRS page.
The test that decides whether a UK group is caught by CSRD
This is the most commercially relevant EU fact for a UK reader, and every UK-facing page that states it states the old numbers.
If you have seen €150 million and €40 million on a UK adviser’s page, those figures were correct until February 2026. Grant Thornton’s cheat sheet and Sweep’s UK guide both still carry them.
Assurance — voluntary here, and lighter in the EU than you were told
No UK regime requires sustainability information to be assured. The standard governing how it is done exists and bites in December 2026.
If you are budgeting for reasonable assurance on a CSRD timetable, that obligation no longer exists. Limited assurance remains.
The global baseline, counted honestly
“Over 40 jurisdictions have adopted the ISSB standards” is two errors in one sentence. Here are both numbers, and what each of them means.
The gap between 40 and 19 is the gap between an intention and an obligation, which is the same gap this whole page is about. The United Kingdom sits in the Foundation’s snapshots group rather than its profiles group precisely because its approach is still subject to consultation — the jurisdiction listing carries no stated total, so any count you see was assembled by someone.
So: three obligations, three intentions, and one date in December 2027.
What follows is the reference material — the frameworks, the principles, the vocabulary, and where each of them actually applies.
Why sustainability reporting matters
Three constituencies drive it, and they want different things — which is why there are six regimes rather than one.
Sustainability reporting frameworks — the comparison
Nine frameworks, what each one is for, and whether it is an obligation anywhere that matters to you.
| Framework | Jurisdiction | Status | Materiality | Basis |
|---|---|---|---|---|
| UK SRS S1 and S2 | United Kingdom | Voluntary; proposed for listed issuers from 2027 | Single (financial) | IFRS S1/S2, per Annex A differences |
| SECR | United Kingdom | Mandatory since 1 April 2019 | Not applicable | SI 2018/1155, within the Companies Act 2006 |
| ESOS | United Kingdom | Mandatory four-yearly; Phase 4 closes 5 December 2027 | Not applicable | SI 2014/1643, SI 2023/1182, SI 2026/701 |
| s.414CB climate disclosure | United Kingdom | Mandatory since 6 April 2022, >500 employees | Single (financial) | Companies Act 2006 s.414CB |
| IFRS S1 and S2 | Global baseline | In force in 19 jurisdictions | Single (financial) | ISSB, 26 June 2023 |
| EU CSRD / ESRS | EU and large non-EU groups | Mandatory from FY2027 (>1,000 employees and >€450m) | Double | Directive 2022/2464 as amended by (EU) 2026/470 |
| TCFD | Global voluntary | Task Force disbanded 2023; structure absorbed by ISSB | Single (financial) | Final Recommendations, June 2017 |
| GRI Standards | Global voluntary | Voluntary | Impact | Universal Standards 2021 |
| SASB Standards | Global voluntary, industry-specific | Voluntary; referenced by IFRS S1 | Single (financial) | IFRS Foundation |
The row that surprises people is TCFD. The Task Force was disbanded in 2023 and its monitoring absorbed by the ISSB — so “TCFD reporting” in the UK now means either the section 414CB duty or the FCA’s Listing Rules, depending on who is asking.
Sustainability reporting standards — where to go next
“Framework”, “standard” and “guidance” are used interchangeably, and the standards themselves are covered in depth elsewhere on this site.
Voluntary frameworks operating in the UK
None of these is required by any UK instrument. All of them still turn up in tenders, investor questionnaires and index submissions.
Sustainability reporting principles
Underneath the frameworks sit a handful of principles that almost all of them share. They are what an assurance provider tests against when the standard is silent.
Guideline, standard, framework — they are not the same word
The vocabulary is genuinely confusing, and the confusion has consequences when someone says you are “not compliant with GRI”.
Disclosure and reporting — the difference that matters
Used interchangeably in ordinary speech, but the UK regimes distinguish them, and the distinction decides where the information goes.
The UK sustainability regulations, as instruments
Every obligation on this page traces to one of these. Named, dated, and linked to the text rather than to somebody’s summary of it.
Environmental reporting specifically
Where the subject narrows from sustainability to environment, the UK requirements get older, more prescriptive and considerably more concrete.
Where it goes in the annual report
“Financial sustainability reporting” is usually a question about placement, and UK law answers it precisely.
ESG reporting requirements in the UK
If you arrived searching for ESG reporting requirements rather than sustainability reporting, the answer is the same six regimes — and one page that goes deeper.
Is sustainability reporting mandatory in the UK?
Partly, and the honest answer depends entirely on what kind of organisation you are.
What good looks like
Not a list of award-winning reports. Four things that separate a report that survives assurance from one that does not.
Where to start — practical sequencing
In order, assuming you are starting from nothing and want the cheapest path to being compliant and useful.
Frequently asked questions
What is sustainability reporting?
Sustainability reporting is the disclosure of environmental, social, and governance (ESG) information about an organisation. It includes climate-related risks and opportunities, environmental impacts, workforce practices, and governance arrangements that affect long-term value creation.
Is sustainability reporting mandatory in the UK?
Partially. SECR (energy and carbon) has been mandatory since 2019 for large companies, and ESOS (energy audits) is mandatory four-yearly for large energy users. Climate-related financial disclosure under section 414CB has been mandatory since 2022 for companies with more than 500 employees. UK SRS is published but voluntary; the FCA has proposed making it mandatory for listed companies from 1 January 2027 under CP26/5, but no Policy Statement has been published and no rule has been made.
What's the difference between SECR and UK SRS?
SECR covers annual energy consumption and GHG emissions disclosure for large companies since 2019. UK SRS covers broader climate-related financial disclosures including scenario analysis, transition planning, and governance — voluntary now, proposed for listed companies from 2027. They do not replace one another: SECR duplication is not relieved by adopting UK SRS.
What is single materiality vs double materiality?
Single materiality (used by UK SRS and IFRS S1/S2) focuses on how sustainability matters affect the company's financial performance. Double materiality (used by EU CSRD) includes both financial effects AND the company's impacts on people and environment.
How does UK sustainability reporting compare to EU CSRD?
UK SRS uses single (financial) materiality and is proposed for listed companies from 2027. EU CSRD uses double materiality and, after the 2026 Omnibus revision, applies to EU undertakings with more than 1,000 employees and over €450m turnover from financial year 2027, plus non-EU groups (including UK groups) with over €450m of EU turnover and a qualifying EU subsidiary or a branch over €200m, from financial year 2028.
What's the role of ISSB and IFRS S1/S2?
The ISSB (International Sustainability Standards Board) published IFRS S1 (general requirements) and S2 (climate-related) on 26 June 2023. These provide the global baseline: around 40 jurisdictions are planning to adopt or use them, and requirements have come into effect in 19. The UK adopts them through UK SRS, which incorporates IFRS S1/S2; the government consulted on six proposed UK amendments in June 2025, and the final Standards' differences from IFRS S1/S2 are set out in Annex A of the government response.
Where do I start with sustainability reporting?
Start by checking if you're in scope for mandatory regimes (SECR, UK SRS, ESOS). For voluntary adoption, begin with UK SRS S2 climate disclosure as it provides the foundation. Assess materiality, establish governance, collect baseline data, and consider phased implementation.
Do I need assurance for sustainability reporting?
Not mandatory under current UK SRS proposals (CP26/5 proposes a statement of whether assurance was obtained, not mandatory assurance). ISSA (UK) 5000 provides the methodology if you choose assurance, effective for periods beginning on or after 15 December 2026. EU CSRD mandates limited assurance; the reasonable assurance requirement was deleted by the 2026 Omnibus directive.
How many UK companies have to do SECR reporting?
About 19,900, according to the Department for Energy Security and Net Zero's post-implementation review of 26 May 2026 — against an original forecast of 11,300. The figure of 11,900 still widely quoted comes from a 2018 impact assessment and is obsolete.
Did the April 2025 company size changes affect SECR?
No. SI 2024/1303 raised the Companies Act size limits to £54m turnover and £27m balance sheet for financial years beginning on or after 6 April 2025, but the SECR thresholds of £36m, £18m and 250 employees sit in Schedule 7 of the 2008 Accounts Regulations in their own right and were not uprated. A company that is medium-sized for its accounts can still be a SECR reporter.
What changed for ESOS in 2026?
SI 2026/701 came into force on 22 July 2026. It removes Display Energy Certificates and Green Deal Assessments as routes to ESOS compliance, adds a zero energy consumption exemption, adds a third progress update, and inserts a new action plan review chapter. The Environment Agency published Phase 4 guidance on 30 July 2026.
Is TCFD reporting being abolished in the UK?
Not the Companies Act duty. Section 414CB is in force, and unchanged since SI 2022/31. What the FCA's CP26/5 proposes to delete is the TCFD-aligned UK Listing Rules, replacing them with UK SRS-based requirements — a different obligation on a different population. Any change to the Companies Act would come through the Modernising Corporate Reporting programme, which has not yet consulted.
Sources
Every figure on this page resolves to one of these. Each entry says what it is for, because a source list that is only titles is a bibliography, not evidence.
- 1UK SRS S1 and UK SRS S2Department for Business and Trade · 25 February 2026The two standards themselves, 45 pages each. The publication date and the documents.back to where this is used
- 2UK Sustainability Reporting Standards (guidance)Department for Business and Trade · updated 25 February 2026The status source: “available for voluntary use, by any entity that chooses to do so.”back to where this is used
- 3CP26/5: Aligning listed issuers’ sustainability disclosures with international standardsFinancial Conduct Authority · 30 January 2026, closed 20 March 2026The proposal, and the Next steps note that still says a Policy Statement is only aimed at.back to where this is used
- 4CP26/5 (full consultation paper)Financial Conduct Authority · January 2026Paragraph 1.3 for the jurisdiction count; paragraph 3.4 for the five UKLR categories; Annex 2 for the 515 and the 89.back to where this is used
- 5Sustainability Reporting Developments: frequently asked questionsFinancial Reporting Council · updated 26 February 2026The only source that states plainly that UK SRS S2 relieves the s.414CB duplication and that SECR duplication is not relieved.back to where this is used
- 6SI 2018/1155 — the Companies (Directors’ Report) and LLPs (Energy and Carbon Report) Regulations 2018UK Parliament · 2018The instrument that created SECR, amending Schedule 7 to SI 2008/410.back to where this is used
- 72026 post-implementation review of the SECR Regulations 2018Department for Energy Security and Net Zero · 26 May 2026Where 19,900 comes from, against a forecast of 11,300 — and the recommendation to retain SECR with amendments.back to where this is used
- 8SI 2026/701 — the Energy Savings Opportunity Scheme (Amendment) Regulations 2026UK Parliament · in force 22 July 2026Regulation 26 omits regulation 34: Display Energy Certificates and Green Deal Assessments are no longer routes to ESOS compliance.back to where this is used
- 9Energy Savings Opportunity Scheme (ESOS)Environment Agency / GOV.UK · updated 16 February 2026Phase 4 dates and the qualification test. Note it has not yet caught up with SI 2026/701.back to where this is used
- 10Companies Act 2006, section 414CBUK Parliament · current to 15 August 2026The climate-related financial disclosure duty, in force and unchanged since SI 2022/31. Subsection (A1) imposes it; subsection (2A) defines what it covers.back to where this is used
- 11SI 2022/31 — the Companies (Strategic Report) (Climate-related Financial Disclosure) Regulations 2022UK Parliament · in force 6 April 2022What inserted s.414CB, and the >500-employee scope test.back to where this is used
- 12IFRS Sustainability Disclosure Standards around the world — use by jurisdictionIFRS Foundation · no date stampTwo ungrouped lists and no stated total. Do not derive a count from it — take the Foundation’s own published figure instead.back to where this is used
- 13Jurisdictional Readiness Assessment Guide added to the ISSB adoption toolkitIFRS Foundation · 24 February 2026“Nearly 40 jurisdictions… requirements in 19 jurisdictions have already come into effect.” The honest split.back to where this is used
- 14Directive (EU) 2026/470 — Omnibus amendments to CSRD scope, timing and assuranceOfficial Journal of the European Union · in force 18 March 2026The €450m / 1,000-employee test, the third-country thresholds, and the deletion of the reasonable-assurance empowerment.back to where this is used
- 15FRC takes steps to support quality and consistency in the assurance of sustainability reportingFinancial Reporting Council · November 2025ISSA (UK) 5000: voluntary, effective 15 December 2026, one UK modification.back to where this is used
- 16GRI StandardsGlobal Reporting Initiative · Universal Standards 2021, effective 1 January 2023The current Universal Standards, and the news feed where the ISSB joint statements land.back to where this is used
- 17GRI and IFRS Foundation reaffirm commitment to complementary disclosuresGRI / IFRS Foundation · 26 May 2026The current statement of how the two standard-setters relate. Supersedes the 2022 MoU as the thing to cite.back to where this is used
- 19IFRS S1 General Requirements for Disclosure of Sustainability-related Financial InformationIFRS Foundation · 26 June 2023The general requirements standard UK SRS S1 is built from.back to where this is used
- 20IFRS S2 Climate-related DisclosuresIFRS Foundation · 26 June 2023, amended December 2025The climate standard, and the December 2025 amendments that the UK incorporated.back to where this is used
- 21Environmental Reporting Guidelines, including mandatory greenhouse gas emissions reporting guidanceDefra / DESNZ · last updated 29 March 2019The document most UK carbon-reporting content paraphrases. Worth knowing how old it is.back to where this is used
- 22SI 2014/1643 — the Energy Savings Opportunity Scheme Regulations 2014UK Parliament · 2014The founding ESOS instrument.back to where this is used
- 23SI 2023/1182 — the Energy Savings Opportunity Scheme (Amendment) Regulations 2023UK Parliament · 2023The Phase 3/4 amendments, including the sterling qualification figures.back to where this is used
- 24SI 2024/1303 — the Companies (Accounts and Reports) (Amendment and Transitional Provision) Regulations 2024UK Parliament · for periods from 6 April 2025The company size uplift to £54m / £27m — which did not touch SECR.back to where this is used
- 25Companies Act 2006UK Parliament · 2006The Act the strategic report, the directors’ report and s.414CB all sit inside.back to where this is used
- 26SASB StandardsIFRS Foundation / SASB · industry-based guidanceIndustry-specific metrics, now inside the IFRS Foundation and referenced by IFRS S1.back to where this is used
- 27CDPCDP Worldwide · annual questionnairesInvestor-driven disclosure. Voluntary, and the reason many UK companies already hold Scope 1 and 2 data.back to where this is used
- 28TCFD Final RecommendationsTask Force on Climate-related Financial Disclosures · June 2017The four-pillar structure every later standard inherited. The Task Force itself disbanded in 2023.back to where this is used
- 29European Sustainability Reporting StandardsEFRAG · 2023 onwardsThe ESRS themselves, and the revision work following the Omnibus.back to where this is used
- 30Corporate sustainability reportingEuropean Commission · currentThe Commission’s own landing page for CSRD as amended.back to where this is used
- 31ISSA 5000 General Requirements for Sustainability Assurance EngagementsIAASB · 2024, effective 15 December 2026The international standard ISSA (UK) 5000 is the UK version of.back to where this is used
- 32RPC opinion — SECR post-implementation reviewRegulatory Policy Committee · 15 May 2026Independent scrutiny of the SECR review. Departmental recommendation: amend, not remove.back to where this is used
- 33Streamlined Energy and Carbon Reporting for academy trustsDepartment for Education · currentAn unlikely but useful primary confirmation that the SECR thresholds are still £36m / £18m / 250 after April 2025.back to where this is used
Three obligations. One deadline that is close. Everything else is a proposal with a date attached.
This page was verified against primary sources on 17 August 2026. Where a figure is contested — the ISSB jurisdiction count, the SECR population — both numbers are given and the source of each is named.