What importers need (for reporting/declarations)
Product CN code, quantity, and country of origin.
Specific embedded emissions (direct + indirect where applicable) per tonne.
Carbon price already paid in origin country (for deduction).
Verified supporting documentation and full audit trail.
What producers provide (and need to prepare)
Installation-specific production routes and activity data.
Verified emissions calculations (aligned with EU methodology from 2026).
Precursor emissions (if relevant).
Methodology evidence and third-party verification (mandatory from definitive phase).
Why “actual” verified data matters
From 2026, actual verified emissions minimise CBAM costs. Where actual data is unavailable/unverified, country-specific default values apply – these include progressive mark-ups (e.g., +10% in 2026, +20% in 2027, +30% from 2028) to incentivise accurate reporting. Defaults are conservative and increase liability exposure.