UK SRS and the ISSB: What UK Companies Need to Know

If you read only one thing about the UK Sustainability Reporting Standards, make it this: they are finalised, they are voluntary, and they are not law. A great deal of commentary online gets this wrong — either ignoring UK SRS entirely or implying it is already compulsory — and for a Finance Director or Head of Sustainability making a reporting decision, getting the status wrong in either direction is costly. This guide sets out exactly where UK SRS stands as at 2 July 2026, how it relates to the global ISSB standards, and what a company caught in the middle of a moving regime should actually do.

What UK SRS is

UK SRS S1 and UK SRS S2 are the United Kingdom’s version of the global sustainability-disclosure baseline created by the International Sustainability Standards Board (ISSB), the standard-setter that sits under the IFRS Foundation. The ISSB published two standards — IFRS S1, covering general sustainability-related financial disclosures, and IFRS S2, covering climate-related disclosures specifically. The UK ran an endorsement process to produce UK-specific versions of those two standards, and the result is UK SRS S1 and S2.

The design intent is a single global baseline. Rather than every jurisdiction inventing its own incompatible disclosure regime, the ISSB standards give investors a common language for sustainability information, and national versions like UK SRS keep only the limited amendments a jurisdiction genuinely needs. For a company that reports internationally, that consistency is the whole value proposition: prepare once, to a framework that is recognised across markets.

Structurally, the standards will feel familiar to anyone who has already produced a TCFD-aligned disclosure. UK SRS S2, like the TCFD framework it builds on, is organised around four pillars — governance, strategy, risk management, and metrics and targets. That continuity is deliberate, and it is good news for in-scope companies, because it means existing climate-disclosure work is a foundation for UK SRS rather than a dead end.

The status, precisely — and dated

Because this is where most content goes wrong, here is the position stated carefully and with its source.

Stat callout — the status, verified. UK SRS S1 and S2 are finalised and available for voluntary use by any entity that chooses to adopt them. The gov.uk guidance was last updated on 25 February 2026. They are not mandatory. Verified against gov.uk, 2 July 2026.

Two further facts complete the picture, and both point to a possible — but not yet decided — future mandatory regime:

• The government has indicated it will consider whether to introduce requirements for certain UK entities to report against the standards. That is a stated intention to look at mandation, not a decision to mandate.
• The Financial Conduct Authority (FCA) consulted on amendments to the UK Listing Rules that would bear on climate and sustainability disclosure for listed companies, with that consultation closing on 20 March 2026. A consultation is a stage in a process, not an enacted rule.

So the honest, defensible summary as at 2 July 2026 is: finalised, voluntary, and under active consideration for a future mandatory regime — but not law today. If a source tells you UK SRS is already compulsory, it is overstating the position, and a compliance decision built on that overstatement is built on sand.

This distinction — what is settled law versus what is proposed — is the single most useful thing we can give a client on this topic, because it is exactly the distinction most content fails to draw. It is the same discipline we apply across the whole reporting stack on our UK ESG compliance service.

What IS enacted, so you know what actually binds you

The reason the voluntary status of UK SRS matters is that it sits alongside duties that are very much enacted and mandatory. It is easy to conflate the whole “climate reporting” space into one blur; in fact some of it binds you today and some of it does not. As at 2 July 2026, verified against gov.uk and legislation.gov.uk:

• SECR (Streamlined Energy and Carbon Reporting) is enacted and mandatory for quoted companies, and for large unquoted companies and LLPs. “Large” is the Companies Act test — you are caught if you meet at least two of three thresholds: 250 or more employees, turnover over £36 million, or a balance-sheet total over £18 million. The disclosure goes in the directors’ report, filed with your accounts. Our SECR reporting hub sets out exactly who is in scope.
• Mandatory TCFD-aligned climate-related financial disclosure under the Companies (Strategic Report) (Climate-related Financial Disclosure) Regulations 2022 is enacted for the UK’s largest traded companies, banks and insurers, plus private companies and LLPs with more than 500 employees and turnover over £500 million — a different and higher threshold than SECR, and not to be conflated with it.
• The net-zero-by-2050 target is statutory, set by the Climate Change Act 2008 as amended in 2019.
• PPN 006 requires a published Carbon Reduction Plan to bid for major central-government contracts above £5 million a year — a current procurement duty, covered in our guide to what ESG tenders and PQQs ask for.

Against that backdrop, UK SRS is the one significant piece that is not yet binding. Understanding that lets you avoid two opposite errors: under-reporting today by ignoring the duties that actually apply, and over-building tomorrow by rushing to a standard no one has yet required.

What this means for your reporting decision

So what should a company actually do about a finalised-but-voluntary standard that might become mandatory? The pragmatic answer is neither “adopt everything now” nor “ignore it until forced” — it is prepare deliberately.

If you are already in scope of mandatory TCFD-aligned disclosure, you are most of the way there structurally. UK SRS S2 shares the four-pillar architecture — governance, strategy, risk management, and metrics and targets — so the sensible move is to build your current climate reporting so that adopting UK SRS later is an extension rather than a rebuild. That means getting the underlying data, boundary and governance right now, in a way that maps cleanly onto the ISSB structure.

If you are a listed company, watch the FCA’s Listing Rule work closely. If a mandatory UK regime does arrive, listed companies are the most likely to be reached first, so the lead time you build now is the lead time you will be glad of later.

If you are a large private group not yet in TCFD scope, UK SRS is not an immediate obligation — but your investors, lenders and largest customers may ask about your readiness regardless, and a credible answer is worth having. The foundation is the same as for everything else: a defensible carbon footprint and baseline and, where value-chain emissions matter, a handle on Scope 3, which is central to UK SRS S2.

Stat callout — the efficient path. Because UK SRS S2 and TCFD-aligned disclosure share the same four pillars, reporting built to today’s mandatory rules can be structured once so that a later UK SRS adoption is an extension, not a fresh start. That is how you avoid paying twice.

The through-line is governance and data quality. A materiality assessment that establishes which sustainability issues are financially significant, a governance framework that gives the board real oversight, and a baseline built on a defensible methodology — the work that our ESG strategy and materiality service delivers — is the work that pays off under whichever regime lands, because both TCFD and the ISSB standards are built around exactly those foundations.

The bottom line

UK SRS S1 and S2 are a genuinely significant development — the UK’s endorsement of a global sustainability-reporting baseline — but their status is frequently misstated, and precision here protects you. As at 2 July 2026 they are finalised for voluntary use, not mandatory, with mandatory adoption under consideration by government and the FCA. Build your reporting on the duties that bind you now — SECR, TCFD-aligned disclosure where you are in scope, the statutory net-zero target, and PPN 006 if you tender — and structure it so that adopting UK SRS later is a step, not a start-over.

For a plain read on which of these actually apply to your business, and how a programme is scoped, see our ESG compliance cost guide and our frequently asked questions, or talk to our ESG reporting and compliance specialists. The regional picture — how these rules land for companies in a specific city-region and its anchor institutions — is set out on our location pages, including London, Manchester and Birmingham.

If a board or an investor is asking where you stand on UK SRS and TCFD-aligned disclosure, the quickest way to a clear answer is a short readiness conversation. Use the enquiry form below, or request a quote, and we will tell you honestly which duties bind you today and what preparing for tomorrow actually involves.

Related reading

• What ESG tenders and PQQs actually ask for — the commercial pressure that often moves faster than the law.
• How to build a carbon baseline — the data foundation that every reporting standard, present and future, depends on.

Government source, verified 2 July 2026: UK Sustainability Reporting Standards (UK SRS) guidance on GOV.UK (last updated 25 February 2026).