Manufacturers evaluating exposure to the proposed downstream expansion of the EU Carbon Border Adjustment Mechanism (CBAM) face a classification step before estimating potential carbon costs. The customs code applied to an imported machine, metal assembly, or construction component can determine whether the product falls within the mechanism. Accurate classification is therefore positioned as a prerequisite for both current compliance and future planning.
CBAM already covers selected processed steel and aluminium products. Certain fasteners, structures, tanks and other fabricated goods cannot be treated as exempt solely because they have undergone further processing. At the same time, the presence of steel or aluminium in a finished product does not automatically place that product within the mechanism.
Combined Nomenclature codes used to determine CBAM coverage
The starting point for determining product coverage is the EU’s Combined Nomenclature (CN), which classifies imported goods. Manufacturers are advised to align the codes shown on actual EU import declarations with their product specifications rather than rely on broad commercial descriptions such as automotive components, machinery, or industrial equipment.
The need for this distinction increases as downstream expansion negotiations progress. The European Commission, Council and European Parliament have put forward different product lists, requiring companies to separate goods already covered by existing rules from those appearing only in proposed legislative annexes.
For an assessment to be auditable, it should document the customs code used, the legal text and version checked, and the date of assessment. This record is intended to support evidence requests from customers and help track impacts when legislation changes.
Mixed-material goods and border definitions affect classification
Classification can be more complex for goods made from multiple materials. Two products with similar purposes may receive different classifications due to differences in design, composition or principal function. Products under the same customs code may also include different proportions of steel or aluminium.
Customs classification and emissions attribution are described as related but separate tasks. The customs code is used to determine whether a product is covered, while the applicable CBAM methodology sets out how embedded emissions and associated obligations are calculated.
Importers also need to establish what exactly crosses the EU customs border. A complete machine, a replacement part and an unfinished assembly may fall under different classifications, depending on how the goods are declared. Shipping arrangements and declarations must reflect the actual goods and applicable customs rules, since artificial changes intended to avoid coverage can increase enforcement risks.
Documentation and tools for managing CBAM exposure
Manufacturers can strengthen their assessment by linking each export product to its import code, EU customer, annual sales volume and principal metal inputs. This approach is described as a practical way to distinguish current CBAM exposure from potential costs under the proposed expansion.
A product-level exposure register can also surface inconsistencies when different customers classify apparently identical products differently. These discrepancies are flagged for investigation before they affect declarations, pricing or contractual negotiations.
Where classification remains uncertain, formal customs advice or a Binding Tariff Information (BTI) decision may provide a more reliable basis than an exporter’s commercial product description. Changes in product design, function or material composition should trigger a review if they could affect the applicable code or CBAM treatment.
Contract implications tied to downstream timing
Customs codes are also relevant for negotiations on how future carbon costs are allocated. A supplier cannot assess an unlimited CBAM-related cost clause without knowing which products it covers, while buyers need comparable clarity when comparing landed costs across suppliers.
The risk is described as particularly significant for fixed-price contracts extending beyond the potential 2028 start date of the proposed downstream expansion. After signing, a manufacturer could find that a product was already covered by existing rules or that the final expansion captures a larger share of sales than expected.
Before calculating a carbon liability, manufacturers need to establish which goods they are selling and how those goods are classified under EU customs rules. This classification work is presented as foundational for credible exposure estimates and more precise contract terms.