Aviation connects the world, but it comes with a significant environmental cost. In response, the International Civil Aviation Organization (ICAO) introduced the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA), a global framework to help airlines manage their environmental impact while enabling sustainable growth.

If you're an airline or a stakeholder navigating CORSIA's obligations, understanding its mechanics and effectively sourcing high-quality carbon credits are critical. In this article, we explain the essentials of CORSIA and how Opna can help you achieve compliance seamlessly, all while supporting impactful climate action.

What is CORSIA?

CORSIA was adopted in 2016 as a pioneering effort to reduce aviation-related greenhouse gas emissions. Its goal is straightforward: to offset any emissions above 85% of an airline’s 2019 emissions baseline, ensuring that international aviation growth doesn’t come at the planet’s expense.

Airlines in CORSIA are required to purchase carbon credits, also known as CORSIA Eligible Emissions Units (EEUs), to offset emissions exceeding the baseline. These credits represent verified reductions in greenhouse gases, generated by projects worldwide.

How does CORSIA work?

CORSIA is being rolled out in phases:

Pilot Phase (2021–2023): Voluntary participation.
First Phase (2024–2026): Mandatory for airlines from participating states.

Second Phase (2027–2035): Expands mandatory participation, with some exemptions for low-emitting states and routes.

Participation: Starting January 2025, 129 states will participate in CORSIA’s first phase. CORSIA applies to emissions from all international flights between member states, excluding emissions that are accounted for via ETS schemes, such as the EU ETS.

Baseline: Airlines must offset emissions exceeding 85% of their 2019 baseline.

Navigating carbon markets: The essentials

To be eligible, CORSIA eligible carbon credits must:

Come from an ICAO-approved program, from one of the six registries listed below (exclusions apply for certain methodologies, such as project level REDD+ credits, when there are concerns around permanence and leakage):

American Carbon Registry (ACR)
Architecture for REDD+ transactions (ART)
Climate Action Reserve
Global Carbon Council
Gold Standard
Verra

Include a Letter of Authorization (LoA) from the host country to ensure no double-counting of emissions reductions.
Be generated from projects started after 2016, with vintages from 2021 or later.

Demand for CORSIA credits is expected to outstrip supply, driving up prices.

Currently, the only project with CORSIA-eligible volumes available for retirement are from the Guyana Jurisdictional REDD+ project under the ART TREES programme, with credits said to be trading at the mid to low $20's/tonne.

Current estimates suggest prices will range from $18 to $51 per tonne during Phase 1 (2024–2026) and could rise to $27–91 per tonne by 2030 as demand intensifies. Airlines will need to act early to secure high-quality credits at competitive prices and avoid compliance risks.

Compliance and risks

Failing to comply with CORSIA comes with significant penalties. Airlines must still purchase credits to cover their obligations and pay additional fines, which vary by country. For instance, the UK has just opened a consultation on legislation that proposes a £100 penalty for each tonne of carbon that an airline fails to cancel on time.

With compliance costs rising, airlines must take a proactive approach to sourcing credits and managing risk.

How Opna simplifies CORSIA compliance

Navigating CORSIA requirements doesn’t have to be overwhelming. At Opna, we specialise in helping airlines meet their offsetting obligations while maximising the environmental and social impact of their investments.

What Opna Offers

Access to High-Quality Projects:
- We source credits exclusively from ICAO-approved programs with strong co-benefits, such as biodiversity protection and community development.
Flexible Financing:
- Airlines can secure credits now and pay later, aligning payments with revenue collected from passengers.
Comprehensive Risk Management:
- Opna guarantees the delivery of CORSIA-tagged credits and provides replacement guarantees for unforeseen issues.
Streamlined Compliance Reporting:
- Our monitoring tools make it easy to track credit retirements and report on compliance, ensuring full transparency.

Investing in sustainable aviation

CORSIA is more than just a compliance requirement—it’s an opportunity for airlines to lead on sustainability while supporting impactful climate projects. However, navigating the program’s technical requirements and volatile markets can be challenging without the right expertise.

Opna is here to bridge that gap. By connecting airlines with high-quality, CORSIA-eligible credits and offering end-to-end risk management, we make compliance simple, cost-effective, and impactful.

Ready to meet your CORSIA obligations with confidence? Contact us today to learn how Opna can support your CORSIA carbon credit strategy.