may I fill in an estimate if I don't have exact figures

Estimates are permitted, but not everywhere and not without a label

Yes, an estimate is permitted — for most sustainability questions, it is even the norm, not the exception. EFRAG's VSME basic module is precisely built on the idea that an SME does not have all scope 3 data at hand. Where exact figures are lacking, you are free to provide an estimate, provided you briefly mention the method: based on turnover, based on a sector average, based on the previous year plus an adjustment. This applies to CO2 figures, to the number of employees at a subsidiary, to energy consumption per location.

For other categories, it is different. Questions about hard business data — the registration number under which the enterprise is registered or annual turnover — should be a verified figure, not an estimate. The same rigor applies to the ten measures of Article 21(2) NIS2 and to the control measures in Annex A of ISO/IEC 27001: you are asked whether a measure has been taken, and "approximately" is then not an answer. In the supply chain file, you can indicate that distinction yourself: a figure with an estimate label is recognized as an estimate, and the system sets "no" as long as no fixed value has been established. You confirm for each answer whether that is correct.

Where the distinction comes from

EFRAG's VSME basic module explicitly names estimates as a permitted entry where exact data is lacking, as long as the basis is clear — this follows from the design of the module under Directive (EU) 2022/2464. For identity and scope data, that space does not exist: those fields are derived from the Business Register, where under the Trade Register Act 2007 a verified value is registered, not an approximation.