International Carbon Registry Updates Program Rules for 2026: CDM to PACM Shift, Verification Changes

The International Carbon Registry (ICR) published its 2026 program update, revising five core documents that govern carbon project requirements, methodologies, and verification. The biggest shift is moving from CDM-based methodologies toward the Paris Agreement Crediting Mechanism. Active CDM methodologies still serve as good practice guidance, but they are no longer the primary basis. The update also tightens rules on leakage, baseline reassessment, downward adjustments, credit ownership, and double counting. Verification rules now require validation and verification bodies to hold ISO 14065 accreditation from an IAF or GHG Accreditation Consortium member. The new rules also add detail on materiality, sampling, site visits, findings, and impartiality. New validation engagements must use version 6.2 of the main requirements from November 1, while earlier engagements can continue under version 6.1 until February 28, 2027. Registered projects adopt version 6.2 at their next verification. ICR's CORSIA eligibility for 2027 to 2029 is still under review. The rule changes follow a public consultation and took effect October 9, 2026.