ESRS E1 greenhouse gas reporting connects climate disclosure to the operational data underneath the business. Scope 1, Scope 2, and Scope 3 totals are only defensible when boundaries, source populations, methods, factors, estimates, and changes are controlled.
The 2026 ESRS revision reduces reporting burden, but it does not remove the need for reliable emissions information where climate is material. Companies should use the applicable final ESRS text for their period and keep the inventory aligned with any concurrent IFRS S2 reporting.
Start with reporting boundaries
Document the legal entities, sites, assets, joint arrangements, leases, and operations included in the sustainability statement. Reconcile the list to the financial consolidation and explain differences created by the greenhouse gas consolidation approach.
Maintain a change log for acquisitions, disposals, reorganizations, and newly identified sources. Boundary changes can affect current totals, comparative information, and base-year recalculation.
Prove source completeness
Build a source register for each scope:
- Scope 1: stationary and mobile fuel, process emissions, fugitive emissions, and relevant land-related sources.
- Scope 2: purchased electricity, steam, heat, and cooling, including contractual instruments used for market-based reporting.
- Scope 3: the applicable upstream and downstream categories, with population and method by category.
Reconcile facilities and accounts to finance, procurement, fleet, property, and production records. Assurance tests often identify missing sources through population comparisons rather than recalculating the reported workbook.
Control emission factors and conversions
For every factor, retain the publisher, dataset, geography, activity, unit, year, global warming potentials, version, and selection rationale. Approve changes and assess whether they require comparative or base-year recalculation.
Lock conversion formulas and test units. Common errors include mixing litres and gallons, gross and net calorific values, kilograms and tonnes, or currencies from different periods in spend-based calculations.
Our guide to emission-factor version control provides a practical governance model.
Make estimates transparent
Missing information does not eliminate the reporting obligation where an estimate is permitted. Record why actual data was unavailable, the estimation method, inputs, assumptions, limitations, reviewer, and replacement plan.
For Scope 3, separate spend-based, activity-based, average-data, and supplier-specific methods. Do not present a supplier’s product carbon footprint as higher-quality evidence without checking its boundary, period, allocation, methodology, and verification status.
Reconcile metrics across disclosures
The same emissions figures may appear in the sustainability statement, transition plan, target progress, EU Taxonomy analysis, CDP response, investor materials, and subsidiary filings. Establish one approved dataset and reconcile every publication.
Explain differences when criteria vary. A statutory facility inventory, product footprint, and ESRS group inventory may all be correct while using different boundaries.
Operate a controlled emissions close
Assign owners and deadlines for source submission, validation, calculation, review, correction, and approval. Record exceptions and their resolution. Freeze the approved version and require formal change control afterward.
Test a sample in both directions:
- Trace reported emissions to activity data, factor, formula, and approval.
- Select source records from the population and confirm they reached the inventory.
The first tests accuracy; the second tests completeness.
Connect E1 to assurance
CSRD sustainability statements require limited assurance, and the EU is developing a harmonized standard based on ISSA 5000. Retain evidence as the process operates instead of building a data room at year-end.
Carbon Impact’s GHG Protocol solution, CSRD solution, and ISSA 5000 workflow connect emissions calculations to the criteria and evidence behind them.
This article reflects information available on August 10, 2026. Confirm the legally applicable ESRS text and assurance requirements. This is general information, not legal or assurance advice.
Sources
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