A carbon credit usually represents one tonne of carbon dioxide—or an equivalent amount of another greenhouse gas—reduced or removed under a defined methodology. Buying a credit does not physically erase emissions at the buyer's location; it finances and records a claimed climate outcome elsewhere.
The three parts of Article 6
Article 6.2 provides accounting and reporting guidance for countries transferring mitigation outcomes toward national climate targets. Article 6.4 establishes a UN-supervised crediting mechanism. Article 6.8 covers cooperation that does not rely on traded carbon units.
Why accounting matters
If both the seller and buyer count the same reduction toward their targets, the climate benefit is double-counted. “Corresponding adjustments” are intended to prevent that in relevant international transfers.
Quality also depends on additionality: would the reduction have happened without credit revenue? Permanence matters for stored carbon, especially forests, while measurement and independent verification affect confidence in the claimed result.
A credit is not a licence to ignore emissions
Carbon markets can direct finance toward mitigation, but credits vary in quality and cannot substitute for cutting avoidable emissions. Buyers should examine the methodology, registry, project documents, safeguards and retirement record.
UN Climate Change explains the official structure on its Article 6 page. Continue with more Explainers and our comparison of sustainable fuel, e-fuel and biofuel.
