The European Union's Carbon Border Adjustment Mechanism is now in its definitive financial phase, actively charging steel importers for embedded carbon emissions. CarbonChain carbon specialist Jack Laing warns that using default emission values instead of verified data can double or triple compliance costs. Importers must collect emissions data throughout 2026, begin purchasing certificates in February 2027, & meet a final declaration deadline of September 2027. A parallel United Kingdom mechanism launches in January 2027, creating dual compliance demands for exporters serving both markets.