Corresponding adjustment risk

If a host country withdraws or revokes authorisation after credits have been issued or even retired, the credits typically lose their CORSIA-eligible designation in the relevant registry (or can no longer be labelled/retired for CORSIA), because the host-country authorisation underpinning eligibility has changed. If the credits have not yet been retired for CORSIA, the registry can remove the CORSIA label/designation. If they have already been retired by an airline buyer, the credits must be compensated (i.e. replaced), and the registries place that obligation on the project developer.

According to the registry deeds, liability for replacing credits that have failed to be adjusted is retained by the project developer.

Under CORSIA (for EEUs issued via Verra VCS or Gold Standard), eligible project types include clean cooking and household energy, energy efficiency, small grid-connected renewables up to 15 MW, waste and methane (landfill, wastewater, manure and similar), industrial process efficiency and fuel switching, and certain land use and forestry activities where not excluded (for example not large-scale REDD+ in REDD+ countries above the programme’s thresholds, unless within specified exceptions).

ICAO approves specific emissions unit programmes to supply CORSIA eligible emissions units. As of the latest ICAO CORSIA eligible emissions units materials, approved programmes include American Carbon Registry (ACR), ART (TREES), Gold Standard, and Verra’s Verified Carbon Standard (VCS), with eligibility scoped by compliance phase and additional programme-specific exclusions. Always check the applicable ICAO compliance period and unit date rules in the transaction documentation

For the 2024–2026 CORSIA compliance period, eligible units are generally those linked to emissions reductions occurring from 1 January 2021 through 31 December 2026, and issued from activities whose first crediting period started in 2016 or later. Exact “eligible unit dates” can differ by programme and sometimes by project category, so the definitive vintage window is the one listed for the relevant programme in ICAO’s CORSIA eligible emissions units document.