It depends on your installation's actual carbon intensity relative to the benchmark. Default values carry a mark-up (10% in 2026, up to 30% in 2028 for steel, aluminium and cement). For a low-carbon site, actual data are an obvious way to save. For a site more carbon-intensive than average, the choice must be quantified: in some cases, the default may cost less in the first year. This is a financial decision rather than a simple formality.
Read the source article: CBAM: the end of free ETS allowances for producers