UK SECR vs. SDR: What Changes for Large UK Companies

If you're a large UK company, you're likely already familiar with SECR. What's newer — and less well understood — is how the UK's broader Sustainability Disclosure Requirements (SDR) regime, and the UK Sustainability Reporting Standards (UK SRS) sitting inside it, relate to what you already do.

SECR: the one you probably already comply with

Streamlined Energy and Carbon Reporting has been in force since 2019. It requires large UK companies and LLPs (generally those meeting two of: more than 250 employees, more than £36 million turnover, more than £18 million balance sheet total) to disclose energy use, GHG emissions, and energy efficiency actions in their Directors' Report. It's narrower than most international frameworks — focused on energy and carbon, filed as part of standard annual reporting, with no separate assurance regime attached.

SDR / UK SRS: the newer, broader layer

Sustainability Disclosure Requirements is the UK's umbrella term for a wider push toward standardized, ISSB-aligned sustainability reporting, sitting across several regulators (the FCA, the Department for Business and Trade, and the Financial Reporting Council). The centerpiece is the UK Sustainability Reporting Standards (UK SRS) — the UK's adaptation of the ISSB's global IFRS S1 and S2 standards.

Key facts as of mid-2026:

• UK SRS S1 and S2 were finalized in February 2026 and are currently available for voluntary use.
• The FCA has been consulting (under reference CP26/5) on making UK SRS-aligned reporting mandatory for listed companies, with the direction pointing toward application from financial years starting January 1, 2027.
• The government has separately signaled it will consult later in 2026 on extending mandatory reporting to large private companies and LLPs — but no formal timeline for that extension has been confirmed.
• Critically: SECR is not being immediately replaced. Companies currently reporting under SECR have no immediate obligation to transition to UK SRS. The two regimes are expected to run in parallel for a transitional period, with any full replacement phased in over time.

What's actually different in substance

• Scope: SECR is a narrow energy-and-carbon disclosure bolted onto the Directors' Report. UK SRS/SDR is a full sustainability-related financial disclosure regime — governance, strategy, risk management, and metrics, aligned with how investors read climate risk into financial statements globally (the same architecture as ISSB, CSRD, and Australia's AASB S2).
• Assurance and governance expectations: UK SRS is explicitly built to require stronger board-level governance narratives, clearer links between sustainability risk and enterprise value, and more robust internal controls than SECR ever asked for.
• Audience: SECR was designed as a compliance minimum. UK SRS is designed to be genuinely useful to investors making capital allocation decisions — which is a different bar for data quality.

What large UK companies should do now

1. Keep filing SECR as normal — it's not disappearing on any confirmed timeline.
2. Map your existing TCFD and SECR disclosures against UK SRS S1/S2 now, even on a voluntary basis, since listed companies are the most likely first group required to comply from 2027.
3. Pay particular attention to Scope 3 data gaps — UK SRS includes a transitional relief provision (Appendix C4 to UK SRS S2) that temporarily eases Scope 3 disclosure, but that relief is time-limited, not permanent.
4. If you have EU operations, check your CSRD exposure separately — UK SRS and CSRD are related but distinct regimes, and post-Omnibus CSRD thresholds may or may not catch a UK parent depending on EU subsidiary size.