CORSIA Explained: Aviation Carbon Offsets Guide 2026

What Is CORSIA?

CORSIA — the Carbon Offsetting and Reduction Scheme for International Aviation — is the ICAO (International Civil Aviation Organization) framework that requires airlines to offset the growth in their CO₂ emissions from international flights above the 2019 baseline. It is the world's first global sectoral carbon market mechanism, covering an industry that contributes approximately 2.5% of global CO₂ emissions and significantly more to total radiative forcing when contrail and non-CO₂ effects are included.

CORSIA operates on an offsetting model: airlines are not required to reduce their absolute emissions (unlike the EU ETS), but must purchase and surrender eligible carbon offset units for every tonne of CO₂ they emit above the scheme's reference level. This design was chosen because aviation's growth trajectory makes absolute emission caps politically and operationally difficult — airlines face rising passenger demand with limited near-term technology alternatives to jet fuel.

CORSIA Phases and Timeline

CORSIA Eligible Units (CEUs) — Which Credits Qualify?

Not all carbon credits qualify for CORSIA compliance. The ICAO Technical Advisory Body (TAB) assesses voluntary carbon standards and programmes against the CORSIA Emissions Unit Criteria — a set of quality requirements covering additionality, quantification, permanence, verification, and double-counting prevention. As of 2026, the following programmes are CORSIA-approved and generate eligible offset units:

SAF Credit Interaction with CORSIA

Sustainable Aviation Fuel (SAF) generates carbon credits through its life-cycle emissions reduction relative to conventional jet fuel. Under CORSIA, SAF use can reduce an airline's offsetting obligation — but the accounting rules are complex. Airlines must use the ICAO SAF methodology to calculate the net emissions benefit of SAF blends, and credits can only be claimed once (avoiding double-counting between SAF credits and CORSIA offsets).

The CORSIA SAF framework is a growing area of compliance complexity. Airlines investing in SAF offtake agreements must ensure their carbon accounting team tracks SAF credit eligibility separately from CORSIA offset procurement to avoid over- or under-reporting. CRBN.CREDIT's Compliance Navigator provides integrated SAF + CORSIA offset tracking for airline sustainability desks.

CORSIA Offset Demand and Price Outlook

CORSIA offset demand is a function of aviation traffic growth above the 85%-of-2019 baseline. As international aviation continues its post-COVID recovery — with IATA projecting full capacity recovery plus 8–12% growth by 2026 — annual CORSIA offset requirements have been rising sharply. Estimates for 2026 CORSIA demand range from 40–75 million tonnes of CO₂, rising toward 150–200 Mt/yr by 2030 as Phase 3 mandatory participation begins.

CORSIA offset prices trade at a premium to generic voluntary credits due to the eligibility restriction — not all VCM credits qualify. The eligible universe is narrower than the total VCM, creating a supply-demand dynamic that supports CORSIA Unit prices above non-eligible equivalents. As of May 2026, CORSIA-eligible units trade at approximately $15–$22/tonne, compared to $5–$10 for non-eligible avoidance credits of similar vintage.

FAQ SECTION (Generates Rich Snippets)

Q: What is CORSIA and how does it work?

A: CORSIA is the ICAO global aviation carbon offsetting scheme. Airlines must offset CO₂ growth above 2019 baseline levels by surrendering CORSIA-eligible carbon offset units. It covers international flights for participating states — representing approximately 88% of international aviation CO₂ as of 2026.

Q: Which carbon offsets are eligible for CORSIA compliance?

A: CORSIA Eligible Units (CEUs) must come from ICAO-approved programmes including Verra VCS, Gold Standard, American Carbon Registry, Climate Action Reserve, Global Carbon Council, and ART-TREES. Credits must meet the CORSIA Emissions Unit Criteria covering additionality, permanence, verification, and double-counting prevention.

Q: Does CORSIA apply to domestic flights?

A: No. CORSIA applies only to international aviation — flights between two different states. Domestic aviation is typically covered by national ETS schemes (e.g., flights within the EU fall under EU ETS) or national carbon pricing.

Q: What is the price of CORSIA carbon offsets in 2026?

A: CORSIA-eligible units trade at approximately $15–$22/tonne as of May 2026, carrying a premium over non-eligible VCM credits due to the restricted eligibility universe. Prices are expected to rise as Phase 3 mandatory participation from 2027 significantly expands offset demand.

Q: How does SAF interact with CORSIA offsetting obligations?

A: SAF use reduces an airline's CORSIA offsetting obligation proportionally to the life-cycle emissions reduction of the SAF blend, calculated using the ICAO methodology. SAF credits and CORSIA offsets must be tracked separately to prevent double-counting — an airline cannot claim the same emission reduction benefit twice.

INTERNAL LINKING STRATEGY