South Korea’s airlines expect to spend a combined KRW 335.4 billion ($237.5 million) on CORSIA-eligible carbon credits for the scheme’s 2024 to 2026 compliance period, yet they have secured credits equivalent to just 3.6% of their 2024 requirements, according to Carbon Pulse. The numbers matter well beyond one country’s aviation sector. They are the first hard figures from a major CORSIA participant showing how little procurement has actually happened, less than eighteen months before offsetting becomes mandatory for most international flights. For credit sellers, exchanges and investors, the demand side of the aviation carbon market is no longer a forecast: it is a quantified, largely unfilled order book.

What the Korean Numbers Show

The expected bill, KRW 335.4 billion or roughly $237.5 million, covers South Korean carriers’ obligations for CORSIA’s first phase, which runs from 2024 through 2026. Against that, airlines have locked in supply covering only 3.6% of their 2024 needs, meaning the overwhelming majority of the requirement is still exposed to whatever the market offers between now and compliance deadlines.

That gap has two readings. The benign one is that airlines are deliberately waiting, expecting more CORSIA-eligible supply to reach the market as host countries issue authorizations and standards finalize insurance pathways. The harder reading is that procurement teams looked at a thin, premium-priced pool of tagged units and found little worth buying at current terms. Either way, a compliance obligation measured in the hundreds of millions of dollars for a single country’s carriers is sitting almost entirely unhedged.

Why the Demand Side Was Always Going to Look Like This

CORSIA, administered by the International Civil Aviation Organization (ICAO), requires airlines to offset the growth in international aviation emissions above a baseline. The first phase applies to flights between volunteering states; from 2027 through 2035, offsetting extends to most international routes, with exemptions for least developed countries, small island developing states and states below 0.5% of international revenue tonne kilometres.

The structural problem is eligibility, not volume. IATA has estimated airlines could need more than 200 million eligible units during the first phase, while only around 38 to 40 million units have been tagged for it so far. Credits must come from ICAO-approved programmes and be protected against double claiming, either through a host-country corresponding adjustment under Article 6 of the Paris Agreement or through approved insurance. Korea’s 3.6% figure is what that bottleneck looks like when expressed as a national airline industry’s procurement ledger rather than a market abstract.

The Supply Plumbing Is Being Built Around the Gap

Two other data points from the same news cycle show the market infrastructure responding to exactly this kind of unmet demand. A Singapore-based exchange that has launched futures contracts on CORSIA-eligible credits and jurisdictional REDD units reported a sharp jump in daily trading in the second quarter, as Carbon Pulse reported, although its losses widened. Rising liquidity in CORSIA-linked derivatives suggests traders are positioning for the demand wave that Korea’s unsecured 96% represents, and are willing to fund that build-out through current losses.

On the supply side, Switzerland and Zambia on Monday authorized an improved cookstove project as a greenhouse gas mitigation activity under Article 6.2 of the Paris Agreement, according to Carbon Pulse. Each such authorization adds to the pipeline of internationally transferred mitigation outcomes that can, once remaining eligibility conditions are met, feed CORSIA demand. The direction is consistent: governments are building authorization processes while exchanges build hedging instruments, and both are racing the same 2027 deadline.

What It Means for Buyers and Developers

For airlines, Korea’s figures are a benchmark for peer pressure. Any carrier in a participating state can now be asked why its secured percentage differs from 3.6%, and the comparison will sharpen as 2026 closes. Procurement teams should expect the premium for tagged, CORSIA-eligible units to widen against untagged voluntary inventory as more airlines move from watching to buying, and should treat early corresponding-adjustment supply as strategically scarce rather than merely expensive.

For project developers and credit sellers, the signal is that eligibility planning converts directly into pricing power. Demand of $237.5 million from one country’s airlines, almost entirely unserved, is the commercial case for pursuing host-country authorization or insurance cover on existing inventory. For investors, the Singapore exchange’s widening losses alongside rising volumes describe the cost of building market infrastructure ahead of compliance demand: capital-intensive now, defensible later.

What to Watch

Three markers will show how the gap resolves. First, whether Korean carriers, and peers in other participating states, accelerate procurement in the second half of 2026 or hold out for new supply. Second, the pace of Article 6 authorizations like the Zambia-Switzerland cookstove activity, and how quickly authorized units clear CORSIA’s remaining eligibility screens. Third, liquidity and open interest in CORSIA-linked futures: sustained growth would confirm that the market expects the shortfall to be bought away at rising prices, while stalled volumes would signal airlines intend to comply late, cheaply, or not at all.