CBAM system boundaries for iron and steel inputs
The European Commission’s latest sector-specific guidance distinguishes between iron ore pellets and inputs such as coke and lime under the EU Carbon Border Adjustment Mechanism (CBAM) iron and steel methodology. The distinction is tied to the legal scope and prescribed system boundaries of CBAM rather than indicating that coke or lime production is emissions-free. Iron ore pellets fall under CN code 2601 12 00 and are covered by CBAM. Lime kilns and coke-oven plants fall outside the defined system boundaries for iron and steel because their outputs are not themselves CBAM goods.
Precursor status in downstream steel calculations
For integrated steelmakers, the guidance affects how emissions are carried through an accounting chain used for CBAM purposes. Iron ore pellets can include verified embedded emissions in downstream calculations as a recognised precursor. By contrast, emissions generated by coke and lime may occur across the wider industrial complex, but those emissions are not carried forward as CBAM precursor values under the iron and steel methodology. This creates an emissions-accounting approach that differs from a conventional cradle-to-gate carbon footprint.
Procurement and evidence requirements for reporting
The precursor distinction also shapes procurement practices and data collection needs. Steelmakers in Serbia and Türkiye sourcing iron ore pellets from multiple origins may need to obtain actual verified emissions data or apply relevant default values for those materials. The same precursor-verification process does not apply to coke and lime within the steel calculation. For importers and producers, identifying the legal status of each input is therefore essential when establishing the evidence required for CBAM reporting.
Direct versus indirect emissions categories
The Commission further specifies that indirect emissions are within scope for agglomerated iron ore, while iron and steel are generally subject to direct-emissions accounting under the current CBAM methodology. This creates a separation between upstream pellet production and downstream steelmaking for calculation purposes. The emissions categories included depend on the product and applicable CBAM rules, rather than on the physical contribution of each input to overall manufacturing. As a result, upstream materials can be treated differently depending on their classification under CBAM.
Targeted supplier data requests under CBAM rules
The clarification highlights how EU importers should request evidence aligned with the statutory calculation. Collecting emissions information for every physical input without distinguishing recognised CBAM precursors from other materials can generate extensive documentation without improving accuracy of the required declaration. A more targeted approach maps each input to its legal classification, identifies the applicable system boundary, and establishes which emissions data must be verified or reported. The guidance also affects how lower-carbon supply chains are assessed within CBAM accounting.
Implications for lower-carbon supply chain accounting
The treatment of precursors influences how upstream changes affect embedded-emissions results used in complex steel goods calculations. Lower-emission pellet sourcing can provide a measurable advantage in the embedded-emissions calculation carried into a complex steel good under the current methodology. Decarbonising coke, lime, and other inputs may still have commercial or broader corporate emissions benefits, but those improvements do not necessarily translate directly into a lower CBAM figure. As CBAM certificate costs become a factor in import economics, the legal treatment of individual precursors will determine which upstream emission reductions directly affect border-cost calculations versus broader industrial decarbonisation objectives.