Closing Aviation's CORSIA Credit Gap: What Irish and Global Airlines Must Do Now

New analysis by BeZero Carbon, the London-based carbon ratings agency, maps the supply and quality gaps facing airlines under the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA). Roughly 32 million eligible credits have been issued against a Phase 1 requirement of 150 million by January 2028 — a gap that is wide but not unbridgeable. For Irish carriers Aer Lingus and Ryanair, the analysis offers a clear diagnosis and a practical agenda.

BeZero's findings make clear that volume alone will not resolve the challenge: quality is equally deficient. The agency rated all assessed credits 'BB' or 'B', indicating a low likelihood of genuine climate impact. Airlines filling compliance gaps with low-rated units risk acquiring environmental liabilities, an outcome disciplined procurement can avoid. The sector faces a tripartite challenge — a supply shortfall, a quality deficit, and an authorisation bottleneck — each with a credible response.

IATA projects that airlines will require between 146 million and 236 million eligible emissions units, with compliance costs forecast at $1.7 billion (€1.47 billion) in 2026, up from $1.3 billion (€1.12 billion) the prior year. Only ten projects globally have secured the host-country letters of authorisation needed to issue CORSIA-eligible credits. The EU ETS review due by July 2026 raises a further regulatory question for Irish carriers: whether CORSIA satisfies Paris Agreement standards.

Future supply offers scant quality reassurance. BeZero estimates only 23 per cent of prospective credits will achieve a 'BBB' rating; most may fail to deliver verified reductions. Sylvera projects credit prices of $25 to $36 (€21.55 to €31.03) per tonne by 2027, rising above $60 (€51.71) where supply remains scarce. Aer Lingus has secured SAF agreements with Gevo and Aemetis from 2026, though SAF cannot substitute for compliance-grade credits across CORSIA's full scope.

The authorisation bottleneck is tractable, provided the industry engages early. Under the Paris Agreement's Article 6 framework, host countries must issue letters of authorisation and apply corresponding adjustments to prevent double-counting. As of early 2026, only seven countries had supplied CORSIA units in this way. Ireland's airports at Dublin, Cork, and Shannon handle large international volumes, and Irish carriers stand to benefit disproportionately as the pool of authorised projects expands.

Three interventions can reduce exposure. First, procurement teams should embed independent ratings from BeZero or Sylvera into all credit purchases, targeting only those rated 'BBB' or above. Second, carriers and industry bodies including IATA and the European Aviation Safety Agency should engage host-country governments to accelerate letters of authorisation and expand eligible supply. Third, airlines should front-load SAF procurement, since each tonne consumed directly offsets CORSIA obligations.

The January 2028 CORSIA deadline is now operationally immediate. BeZero Carbon's analysis confirms the voluntary carbon market cannot meet aviation's compliance demand at the required scale or quality. Ireland's carriers, exposed across high-volume transatlantic routes, must act now. Procurement discipline, accelerated SAF investment, and engagement with host-country authorisation processes are the levers available. Whether CORSIA becomes a credible instrument or a cautionary tale depends on how quickly the industry responds.

(The views expressed by the writer are his/her own and do not necessarily reflect the views or positions of BusinessRiver.)