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 assigned to an imported machine, metal assembly, or construction component can determine whether the product falls within the mechanism. Accurate classification is therefore positioned as essential 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 automatically exempt solely because they have undergone further processing. At the same time, the presence of steel or aluminium in a finished product does not by itself mean the product is covered.
Combined Nomenclature codes as the starting point
The classification process begins with the EU’s Combined Nomenclature (CN), which is used to classify imported goods. Manufacturers are expected to reconcile the codes shown on actual EU import declarations with product specifications. This approach is described as preferable to relying on broad commercial descriptions such as automotive components, machinery, or industrial equipment.
The need for this distinction increases as negotiations on downstream expansion progress. The European Commission, Council and European Parliament have proposed different product lists. Companies are therefore required to separate goods already covered under existing rules from those that appear only in proposed legislative annexes.
An effective assessment should document the code used, the legal text and version against which it was checked, and the date of assessment. The documentation is intended to support an audit trail when legislation changes or when customers request evidence for suppliers’ conclusions.
Mixed-material products and what crosses the border
Classification can be more difficult for goods made from multiple materials. Products with similar purposes may receive different classifications due to differences in design, composition or principal function. In parallel, products under the same customs code may still contain different proportions of steel or aluminium.
Customs classification and emissions attribution are described as related but separate exercises. The customs code is used to determine whether a product is covered, while the applicable CBAM methodology determines how embedded emissions and associated obligations are calculated.
Importers must also establish precisely what crosses the EU customs border. A complete machine, a replacement part and an unfinished assembly may fall under different classifications. Shipping arrangements and declarations are expected to reflect the actual goods and applicable customs rules, with artificial changes intended to avoid coverage creating additional enforcement risks.
Registers, advice tools and contract implications
Manufacturers can strengthen their assessment by linking each export product to its import code, EU customer, annual sales volume and principal metal inputs. This linkage 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 highlight inconsistencies when different customers classify apparently identical products differently. Such discrepancies are described as warranting 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 to product design, function or material composition should trigger a review if they could affect the applicable code or CBAM treatment.
Customs codes affecting future carbon cost allocation
Customs codes are also relevant for negotiations over allocation of future carbon costs. A supplier cannot assess an unlimited CBAM-related cost clause without knowing which products it covers. Buyers are described as needing similar clarity when comparing landed costs and evaluating competing suppliers.
The risk is particularly significant for fixed-price contracts extending beyond a potential 2028 start date for downstream expansion. A manufacturer could find after signing that a product was already covered by existing rules or that the final expansion captures a substantially larger share of its sales than anticipated.
The documentation of customs classification is presented as foundational for credible CBAM exposure estimates and more precise contract terms. Before calculating a carbon liability, manufacturers need to establish exactly which goods they are selling and how those goods are classified under EU customs rules.