Navigating ICAO’s CORSIA in the First Phase

Introduction

As CORSIA enters its first phase (2024–2026), significant changes to compliance requirements have been introduced effective in 2024, marking a shift in regulatory standards and expectations; the most notable being the shift in the baseline to 85% of 2019 CO₂ emissions subject to offsetting requirements. With a likely positive sectoral growth factor (SGF), aircraft operators will need to cancel emission units for the coming years and submit an emission unit cancellation report (EUCR) for the first phase (2024–2026). To meet these requirements, operators can also use fuels eligible under CORSIA and benefit from the resulting reductions. For more information on CORSIA, click here

Activities for 2025

January 1 through December 31, 2025: Monitor emissions from international flights in accordance with ICAO Annex 16, Volume IV, Part II, Chapter 2, Section 2.2.
January 1 through April 30, 2025: Compile the CO₂ emissions data for 2024 into an emissions report and collaborate with an independent verification body in accordance with ICAO Annex 16, Volume IV, Part II, Chapter 2, Section 2.4.
April 30, 2025: Submit the verified emissions report and verification report to the state.

Developments in CORSIA

During the pilot phase (2021–2023), the sectoral growth factor (SGF) for each year was 0.0, meaning that aircraft operators had no offsetting obligations for this period and therefore did not need to submit an Emissions Unit Cancellation Report (EUCR) in 2025.

The second compliance cycle and first phase (2024–2026) began in 2024, with a baseline of 85% of 2019 CO₂ emissions, representing a 15% reduction. This baseline remains in effect until 2035, which is likely to result in a positive SGF for 2024, 2025, and 2026. If this is confirmed, aircraft operators must offset their emissions for 2024–2026 by canceling equivalent emission units, which requires the submission of the first EUCR. Operators can download the EUCR template here. At the end of the compliance period (2024–2026), if the operator’s total offset requirement is less than 3,000 metric tons of CO₂, the operator is exempt from offsetting for that compliance period.

To meet the offsetting requirements, operators must purchase and cancel CORSIA-eligible emission units provided by emission unit programs approved by the ICAO Council. For the 2024–2026 compliance period, there are currently six approved programs that meet the established criteria and standards.

Since offsetting is likely to be required in the coming years, operators may consider using CORSIA-eligible fuels to reduce their offsetting requirements; these are fuels certified under the CORSIA Sustainability Certification Scheme. These fuels can be used to claim emission reductions that are reflected in the operator’s final offsetting requirements. If an operator wishes to claim CEFs, it must include additional information with the emissions report using the provided template. Click here for more information about CORSIA-eligible fuels (CEFs).

Compliance with Offset Requirements in the First Phase (2024–2026)

Cancel emission units upon receipt of the State’s final offset requirements for the 2024–2026 compliance period by January 31, 2028 (or within 60 days of notification by the State for the year 2026), as specified in ICAO Annex 16, Volume IV, Part II, Chapter 4, Section 4.2.
No later than February 7, 2028, the aircraft operator shall request that its cancellation of CORSIA-eligible emission units for the 2024–2026 period be published on the respective public website(s) of the CORSIAregister (or registers) of eligible emission units, in accordance with ICAO Annex 16, Volume IV, Part II, Chapter 4, Section 4.2.2(b).
prepare, verify , and submit the emission unit cancellation report for the 2024–2026 period by April 30, 2028, in accordance with Annex 16, Volume IV, Part II, Chapter 4, Section 4.4.

Conclusion

According to the latest update from ICAO, 129 countries have confirmed their participation in the first phase of CORSIA implementation. This development underscores the international aviation sector’s commitment to meeting the emission targets set by the Council, further highlighting the importance of compliance with CORSIA. 2024 is likely to be the first year that offsetting will take place on such a large scale, and this calls for careful planning on the part of aircraft operators.

Contact Normec Verifavia for verification of your CORSIA Emissions Report and Emission Unit Cancellation Report. Click here for more information about CORSIA on our website. Stay compliant, stay ahead of the curve.

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