SME emissions data under CSRD: what is required and how to answer

Two readers land on this page: a large company working out how much emissions data it needs from small suppliers under CSRD, and a small supplier that has just been asked for it. The answer is different for each, and neither answer is "collect everything".

Most of the worry about SME emissions data rests on one assumption, that a CSRD report needs a primary figure from every supplier on the ledger. ESRS 1 does not ask for that, and the requests that reach a small supplier are usually broader than the standard behind them.

CSRD's scope and timetable have been amended since this article first went up, including how smaller undertakings are treated. Read the current thresholds from the directive text or from your advisers rather than from a blog post, this one included.

What does CSRD actually require about SME emissions data?

ESRS 1 lets an undertaking report value chain information it does not hold, provided it explains the gap. The provision covers the first three years of that undertaking's own sustainability reporting under ESRS, and it is a disclosure requirement rather than an exemption. Paragraphs 132 to 135 carry it.

The standard says:

"For the first 3 years of the undertaking's sustainability reporting under the ESRS, in the event that not all the necessary information regarding its upstream and downstream value chain is available, the undertaking shall explain the efforts made to obtain the necessary information about its upstream and downstream value chain, the reasons why not all of the necessary information could be obtained, and its plans to obtain the necessary information in the future."

A reporter inside that window documents three things:

• The efforts made to obtain the information
• Why some of it could not be obtained
• The plan to obtain it in future

ESRS 1 also allows a reporter inside that window to "limit upstream and downstream value chain information to information available in-house, such as data already available to the undertaking and publicly available information". Publicly available is the operative phrase, and it is why an organisation with a public emissions profile gets counted without answering a single survey.

The standard names the difficulty directly: "Obtaining value chain information could also be challenging in the case of SMEs and other upstream and/or downstream value chain entities that are not in the scope of the sustainability reporting required by Articles 19a and 29a of Directive 2013/34/EU."

Which organisations is emissions data worth asking for?

Rank your suppliers by spend and by sector emission intensity, then ask the top of that list. The ranking decides materiality, not company size. A small specialist manufacturer can carry more emissions than a large software vendor on the same spend, so filtering by size sends requests to the wrong organisations.

Two things follow for the reporter. Requests into the long tail cost goodwill and return little, and modelled data on that tail is usually enough for the report. Both hold whether you are looking at suppliers or at portfolio companies, because the concentration question is the same one.

Our guide to the Corporate Sustainability Reporting Directive covers the wider reporting requirements.

How do you get supplier emissions data without sending another survey?

Start from what is already published, and ask only where the answer changes your number. DitchCarbon provides verified emissions data for over 2 million organisations, so procurement, sustainability and finance teams can measure and act on supply chain and portfolio emissions from one source. Four steps, in order:

1. Rank before you ask. Spend and sector intensity first, so requests reach the organisations that move the total.
2. Fill the rest with published and modelled data. Sector emission factors from published sets such as CEDA, DEFRA and EPA give you a starting figure you can explain, refined as primary data arrives.
3. Match the entity, then keep the provenance. Entity resolution against DUNS, LEI and ISIN identifiers ties a figure to the right legal entity, and every figure carries its source and change history, which is what an auditor follows. The DitchCarbon Portal calculator is verified to ISO 14064-3, limited assurance, by UL Solutions, renewed annually, and the report sits in our trust centre.
4. Engage the organisations that matter, with the work half done. A request that arrives prepopulated with a supplier's own published data gets a better response than a blank survey, because you are asking for a correction rather than a project. A recent deployment reached about 60% of a large supplier base within 2 weeks.

That is the route to numbers you can defend within 2 weeks: audit-ready output backed by the ISO 14064-3 verification above, and auditable in the way a third party auditor asks about it, with every figure traceable to its source and coverage gaps shown rather than hidden. Supplier engagement is where the remaining requests go.

What should you send when a customer asks you for emissions data?

Answer once, in a place your next customer can find, then point every later request at it. Five routes, and the first one is free:

1. Claim your company profile. Your organisation probably already has an emissions profile in our data. Claim it, correct what is wrong, and add what only you hold. It is free, you do it yourself, and any customer using DitchCarbon then sees your figures instead of a model.
2. Reuse an EcoVadis scorecard. If you have been through EcoVadis, upload the scorecard and it becomes structured emissions data instead of a PDF your customer has to interpret.
3. Reuse a CDP response. A completed CDP disclosure already holds most of what the customer is asking for. Upload the response rather than retyping it into someone else's template.
4. Let the questionnaire be filled from what you have. When a customer sends its own form, the survey responder completes it from your existing data, so the tenth request costs you a review rather than a week.
5. Say what you do not have. A stated boundary and method, with the gap named, beats a confident number nobody can trace. Reporters inside the ESRS window have to explain gaps anyway, so "not measured yet, and here is the plan" is genuinely usable to them.

If you are the supplier answering, you are also the customer asking. The company filling in a questionnaire this week has its own ledger of suppliers and the same Category 1 problem one tier down, which is why the profile you claim and the supplier data you buy sit on the same verified layer. Answering well is practice for asking well.

Neither side of the request needs a perfect data set. The reporter needs a ranked list and a documented method. The supplier needs one published answer it can reuse. ESRS 1 leaves room for both, and whether any particular report complies is a determination for the reporter and its auditor.

Reviewed 29 July 2026. The regulatory position here is stated from ESRS 1 as published. CSRD scope and timing for smaller undertakings have been amended and are not restated here.

Being asked for emissions data? Claim your company profile, it is free. Collecting it? Request a walkthrough and bring your own supplier list.