The Complete Quarterly CBAM Reporting Guide

Quarterly CBAM reporting is the core obligation under the EU Carbon Border Adjustment Mechanism. This guide explains exactly how to prepare, calculate, and submit each quarterly report.

Why Quarterly Reporting?

CBAM uses a quarterly reporting cycle to:

• Track seasonal variations in production and imports
• Enable timely compliance monitoring
• Align with the EU ETS quarterly compliance cycle
• Allow regular adjustments to emission calculations

Each quarter stands alone — you cannot carry forward excess emissions or under-report from one quarter to another.

Preparing for Each Quarter

30 Days Before Quarter End

• Review import data for the current quarter
• Request emission data from suppliers
• Check for CN code changes (updated annually)
• Verify your product catalogue is complete

15 Days Before Quarter End

• Enter emission data into your reporting system
• Calculate embedded emissions for each product
• Review for anomalies or unusual values
• Generate draft report

Day 1 of Submission Window

• Finalise report
• Export XML for registry submission
• Save PDF for your records
• Submit through CBAM Transitional Registry

Data You Need Each Quarter

Product Data

• Product name and description
• CN code (8-digit)
• Quantity imported (tonnes or kWh)
• Country of origin
• Production method (if relevant)

Emission Data

• Direct emissions per tonne
• Indirect emissions per tonne
• Emission factor source (default or actual)
• Carbon price paid (if any)

Sample Quarterly Report Data

Product	CN Code	Quantity (t)	Origin	Direct (tCO₂e/t)	Indirect (tCO₂e/t)	Total (tCO₂e)
Steel rebar	721420	120	Turkey	0.535	0.137	80.64
Aluminium ingot	760110	45	Canada	1.514	0.423	87.17
Cement clinker	252310	200	Egypt	0.723	0.089	162.40

CbamTrack's dashboard shows your quarterly data in a similar table, ready for review and export.

Common Quarterly Challenges

Supplier Data Delays

Start requesting data 4–6 weeks before quarter end. Use default factors if supplier data is not available by the deadline.

Product Code Changes

CN codes are updated annually. Always verify you are using the current year's codes. CbamTrack automatically updates its CN code database.

Inconsistent Product Naming

Use standardised product names across all quarters. This enables accurate quarter-over-quarter comparisons and anomaly detection.

Verification and Audit

Each report should be internally verified before submission:

1. Quantity check — Do import quantities match shipment records?
2. Factor check — Are emission factors appropriate for the product and origin country?
3. Completeness check — Are all CBAM-covered products included?
4. Trend check — Are emissions consistent with previous quarters?

CbamTrack's audit trail logs every change and provides a complete revision history for compliance verification.

FAQ

What if I discover an error after submission? Errors can be corrected within two months of the deadline. Submit an amended report through the registry.

Do I report actual shipments or ordered quantities? Report actual import quantities based on customs declarations for the quarter.

How do I handle returned or rejected goods? Only goods that clear EU customs are reportable. Returned or rejected goods are excluded.

Can I automate my quarterly report generation? Yes. CbamTrack supports scheduled auto-generation of quarterly reports for Professional plan users, with automatic data aggregation and template-based formatting.