UK SRS: what your large customers will ask you for

UK SRS (UK Sustainability Reporting Standards) are the UK’s versions of the global ISSB standards, published by the Department for Business and Trade on 25 February 2026. They do not apply to SMEs directly. But listed companies reporting under them must disclose their Scope 3 emissions, which include their suppliers, so expect large customers to ask you for your carbon footprint, how you calculated it and what you plan to do next.

If a customer has mentioned “UK SRS” or “ISSB” in an email and you are not sure what it means for you, you are not alone. The short version: you need a credible carbon footprint, updated every year.

What is UK SRS?

There are two standards, both available on gov.uk:

• UK SRS S1 sets general requirements for disclosing sustainability-related risks and opportunities.
• UK SRS S2 covers climate-related disclosures: governance, strategy, risk management, and metrics and targets, including greenhouse gas emissions.

They are based on the International Sustainability Standards Board’s IFRS S1 and S2, with a small number of UK amendments. Our UK SRS glossary entry has a one-paragraph summary.

The standards themselves are voluntary. Any company can use them. What makes them mandatory for some is regulation.

Who actually has to use UK SRS?

The Financial Conduct Authority finalised its rules in Policy Statement PS26/19 on 30 September 2026. In-scope listed companies must report against UK SRS on a “comply or explain” basis for accounting periods starting on or after 1 January 2027, with first reports in 2028.

There are transitional reliefs: one year for Scope 3 emissions, and two years for the wider non-climate disclosures in S1. So for a listed company with a calendar financial year, Scope 3 disclosure applies from its 2028 financial year.

Separately, SECR still requires quoted and large unquoted companies to report energy use and emissions. Most SMEs are outside both regimes. There is no proposal to require UK SRS reporting from SMEs.

Why it still matters to a small supplier

Under UK SRS S2, companies disclose their Scope 3 emissions: the indirect emissions in their value chain. For many businesses, that includes everything they buy, which means everything their suppliers emit.

The standard does not leave this to guesswork. It asks companies to prioritise inputs based on direct measurement, data from specific activities in their value chain, timely data and verified data. In plain English: data from actual suppliers beats a generic estimate.

That is why your customer is asking. If you cannot give them a figure, they may estimate your emissions from how much they spend with you. A spend-based estimate does not reflect anything you have done to reduce your emissions, so providing your own figure is usually in your interest.

What will customers actually ask for?

Requests vary, but expect most of these:

• Scope 1 and Scope 2 emissions in tCO2e for your latest financial year. Scope 2 is often requested both location-based and market-based.
• The method. GHG Protocol, the conversion factors used, and the reporting period.
• Scope 3, sometimes. Larger customers may ask for your main categories, or at least business travel and waste.
• Emissions attributable to them. Often a share of your total, allocated by revenue.
• Targets. Do you have a reduction target or a net zero commitment?
• Climate risks. Occasionally, whether your sites face flooding or heat risks that could disrupt supply.
• Trends. Year-on-year change, once you have more than one year of data.

Some will use their own spreadsheet. Others will point you at a platform, or ask you to report in line with the EU VSME standard, which was designed as a common format for SME data requests.

How to prepare, step by step

1. Measure a baseline. Pick your last financial year and calculate your Scope 1 and Scope 2 emissions. An ESG Now report does this from plain-English questions about your energy, vehicles and travel.
2. Document the method. Customers reporting under UK SRS need to explain their data sources. A footprint that states its standard, factors and assumptions saves them work.
3. Be clear about what is in and out. The ESG Now footprint covers heating fuels, company vehicles, refrigerants, electricity, EV charging, water, waste, courier deliveries and business travel, with estimates of commuting, homeworking and, optionally, purchased goods from spend. It does not include inbound freight paid for by suppliers or downstream categories such as the use of products you sell. Say so in your response.
4. Set a simple target. Even a modest Scope 1 and 2 reduction target answers a question most customers ask.
5. Repeat annually. Customers need a new figure each year. Doing it at the same time each year keeps things simple.

A quick worked example

A 15-person design agency uses 12,000 kWh of electricity and 18,000 kWh of gas a year in a rented office, with no company vehicles. Using the 2026 UK factors of roughly 0.13 kg CO2e per kWh for electricity and 0.18 for gas, that is about 1.6 tCO2e of Scope 2 and 3.3 tCO2e of Scope 1, so around 4.9 tCO2e before travel and waste. If one large customer makes up 25% of its revenue, the share attributable to that customer is roughly 1.2 tCO2e.

The agency now has a figure to give, a method to explain and a baseline to improve on. That is all most customers want.

What about the climate risk questions?

UK SRS S2 asks reporting companies about climate-related risks and opportunities, and some will push a light version of this down to key suppliers. Do not let it throw you. For a small business, the honest answer is usually short and practical:

• Is your site at risk of flooding? The GOV.UK long term flood risk checker shows the long term risk for your area in England in a couple of minutes, with links for Scotland, Wales and Northern Ireland.
• Could you keep supplying if your premises were out of action? Mention backups, remote working or a second supplier.
• Are your own costs exposed to energy prices or carbon policy? A sentence on your energy contract and any plans to cut use is enough.

Nobody expects scenario analysis from a 15-person firm. They want to know you have thought about it.

Getting ahead of the request

You do not need to wait for a customer to ask. Having a current ESG report ready means you can reply to the next request in minutes rather than weeks. Start your free report and most office-based businesses finish in 20 to 30 minutes. Our supplier questionnaires hub has more on handling customer requests.