A carbon figure is easier to review when someone can trace it back to the activity record, reporting period and calculation method. An evidence register gives that trail a consistent home.
Start with the request and the boundary
Keep the customer request or reporting brief with the register. Record the legal entity, sites and period covered, and identify who will approve the final information. A document for one subsidiary or year should not quietly become evidence for the whole group.
Give each source a useful identity
For each invoice, ledger extract or supplier response, record a unique evidence ID, document name, owner, coverage period, activity unit and review status. Link the relevant calculation rows to that ID. Keep a note of estimates, exclusions and unresolved questions.
A simple example is a gas invoice recorded in kilowatt-hours. The calculation needs a compatible factor and the correct calorific-value basis. A total without its unit and source is difficult to reproduce.
Keep factors and activity data separate
The UK government publishes annual conversion factors for company reporting. Its 2026 set converts activity such as fuel, electricity and travel into emissions. Record the factor version, category, unit and source reference alongside the calculation. Read the guidance for the selected activity rather than assuming a familiar number still applies. Source: DESNZ 2026 conversion factors.
Make missing information visible
Use clear states such as received, estimated, awaiting clarification and approved. An empty record is not evidence of zero emissions. Record who will resolve the question and when the answer is needed.
Before reporting, reconcile the activity to its source, check units and periods, screen the relevant emissions sources and obtain the agreed review. A well-organised register supports that process; it does not by itself establish a complete inventory or independent assurance.
VerdeSync offers a focused review of carbon-data and procurement-evidence workflows. Discuss your evidence needs.
