A supplier sustainability questionnaire usually arrives as a spreadsheet, with a deadline and no explanation. The person who receives it is rarely in sustainability. They are in finance, operations or sales, and they have been told to "fill this in by Friday".
Why the supplier sustainability questionnaire exists
Large EU companies report on their value chains, so they need data from the businesses that supply them. They cannot collect it any other way, which is why the request lands on suppliers in the Western Balkans in the same format it goes to everyone else. It is a condition of keeping the account, not a sustainability project.
What it usually asks for
Almost every real questionnaire comes down to Scope 1 and Scope 2 done properly, plus one or two Scope 3 categories that the customer names. Scope 1 is the fuel you burn, including process emissions. Scope 2 is the electricity and heat you buy. The rest of the form is usually context: your boundary, your method and your reporting year.
Read the request before you open the spreadsheet. Answer what it asks for and state the boundary for everything else. See the fifteen Scope 3 categories if the form uses terms you do not recognise.
What to prepare first
- A list of your facilities, one for every site with its own electricity bill.
- Twelve months of electricity invoices per facility. Scope 2 is usually your largest line in this region.
- Fuel purchase records for heating, generators and vehicles.
- Monthly production volumes, if you are an industrial site.
The full list, with what to check before you send anything, is in the GHG inventory checklist.
How long it takes
For a company with one to three facilities, the realistic path from first login to a finished report is about five working days, if the invoices are to hand. The five-day onboarding plan sets out what to do on each day. The slow part is almost always finding the paperwork, not entering it.
If your customer mentions VSME
VSME is the EU's voluntary reporting standard for smaller companies, recommended by the European Commission on 30 July 2025. The Commission's stated aim is that large companies should ask SMEs for what VSME covers instead of sending each supplier a different questionnaire. If a customer names it, ask which module they expect. The emissions part still needs a calculation you can defend; VSME explained covers what it does and does not include.
Send a number you can defend
The question behind every questionnaire is whether the customer's reviewers will accept your answer. A traced figure with a stated boundary is accepted. A rough figure with no source is questioned, and so is the rest of your form. Karbon360 keeps the document, the emission factor and its version behind every figure, so the answer survives the follow-up. A free estimate shows the size of the job before you commit to it.