What UK SRS and SECR Mean for Small Suppliers

If you run a small or medium-sized business in the UK, the names "UK SRS" and "SECR" probably don't appear on your compliance radar. You're right that they don't apply to you directly — the thresholds sit well above where most SMEs operate. But they're shaping what your customers are asking you for, and the gap between "not legally required to report" and "not going to be asked for data" is closing fast.

SECR: what the UK already has in place

Streamlined Energy and Carbon Reporting (SECR) has been mandatory since 2019. It applies to UK quoted companies and large unquoted companies and LLPs — broadly those meeting at least two of: 250+ employees, £36m+ turnover, £18m+ balance sheet total.

Under SECR, those companies must include in their annual report: UK energy use in kWh (gas, electricity, and transport fuel), associated Scope 1 and 2 greenhouse gas emissions, and at least one energy intensity metric such as kgCO₂e per £m revenue. Scope 3 is encouraged but not currently mandatory under SECR — though many companies report it anyway, partly to show a complete picture and partly because their own customers and lenders are asking for it.

The direct effect on smaller suppliers: the companies subject to SECR need to account for their Scope 3 (Category 1: purchased goods and services) to complete their footprint, and their Scope 3 is substantially made up of what they buy from their supply chain. Even though you don't report under SECR, the pressure lands on you via their reporting process.

UK SRS: where things are heading

UK Sustainability Reporting Standards (UK SRS) are the UK's version of the international IFRS Sustainability Disclosure Standards — specifically IFRS S1 (general sustainability-related financial disclosures) and IFRS S2 (climate-related disclosures). The UK government endorsed both standards in July 2024, adapted for the UK context.

UK SRS S2 puts climate disclosures on a significantly more demanding footing than SECR: Scope 3 is central rather than optional, and the framework is structured around climate-related risks, opportunities, and strategy rather than a straightforward emissions tally. Mandatory application is being phased in, starting with large premium-listed companies, with broader rollout expected to follow. The direction is clear — UK-listed companies will face a disclosure regime broadly comparable in ambition to CSRD over the coming years.

What this means if you're a smaller supplier

Neither SECR nor UK SRS applies to most SMEs directly. But both create a systematic demand for supply-chain data from the large companies that are in scope — and that demand flows to their suppliers.

When a large UK customer needs to account for its Scope 3 under SECR or UK SRS, they need to know the emissions associated with what they buy from you. In practice, they may ask for:

• Your company's Scope 1 and 2 emissions (and, increasingly, Scope 3)
• A carbon intensity figure per unit or per £ of spend
• Evidence of a reduction plan or target

In the EU, the Omnibus directive introduced a value-chain cap that limits what CSRD-reporting companies can demand from sub-1,000-employee suppliers — requests are capped at a voluntary standard rather than a full CSRD-grade inventory. You can read the full picture in our CSRD Omnibus guide. The UK doesn't yet have an equivalent statutory cap. UK companies are expected to apply proportionality, but there's nothing preventing them asking for more — and the ask tends to grow as their own reporting obligations tighten.

The practical position for smaller UK suppliers: you should be ready to provide a credible Scope 1, 2 and 3 number on request, expressed in tCO₂e, with a stated methodology. You don't need to be ready for a full audit. You need a number you can stand behind when a customer or tender asks for it.

The right time to prepare is before you're asked

The businesses that get caught out aren't those that can't produce the data — they're the ones that have never thought about it before a deadline lands. If a customer questionnaire, a public-sector tender, or a lender's ESG review asks for your carbon footprint and you have no answer, the cost is real: a lost contract, a delayed process, or a scramble through a months-long data exercise at the worst possible time.

The fastest route to a defensible Scope 3 estimate is the spend-based approach — using your accounting data and published emission factors to estimate the emissions embedded in what you buy. It's the recognised starting point for smaller organisations and it uses data you already have. We cover exactly how it works in how to calculate Scope 3 from spend data. And for businesses that bid for public sector contracts, our Carbon Reduction Plan compliance guide covers the pass/fail requirements under PPN 006.

SpendToScope connects to Xero, Sage, or Microsoft Business Central and builds a whole-business Scope 1, 2 and 3 footprint from your existing accounts — so the number exists, it stays current, and you can hand it over without a project.

The bottom line

• SECR (mandatory since 2019) requires large UK companies to report Scope 1 and 2, with Scope 3 encouraged. Supply-chain data requests are already flowing from it.
• UK SRS (endorsed 2024, mandatory rollout starting with listed companies) places Scope 3 at the centre. The timeline is firming up.
• Neither applies directly to most SMEs, but both create pull from large customers for supply-chain emissions data — and that pull is intensifying as reporting deadlines approach.
• The right response is a credible, current Scope 1, 2 and 3 number, ready before anyone asks for it.