ARC’s August 2026 data shows a pattern worth pausing on. NDC transactions accounted for 21.5% of total ARC-settled transactions in August, while 1,221 travel agencies reported NDC activity, the highest agency count of the year so far. The two numbers tell different stories.
The NDC share has largely stopped climbing. A year ago, NDC represented 16.5% of ARC-settled transactions in January 2025. By January 2026, that figure had reached 20%, a five-point increase in twelve months. Since then, the curve has flattened: June came in at 21.6%, July slipped to 21.2%, and August recovered to 21.5%. Across three consecutive months, NDC’s share has stayed within a narrow 0.4 percentage-point range, a very different pattern from the steady gains seen through most of 2025.
What has not flattened is participation. The number of agencies reporting NDC transactions rose from 1,207 in January to 1,221 in August, moving between roughly 1,186 and 1,221 in the months between. More agencies are doing NDC business each month, even as the proportion of total ARC-settled transactions flowing through NDC has stayed broadly unchanged.
That divergence is more revealing than the headline percentage on its own. It suggests the U.S. market may be entering a different phase of adoption. The first stage was driven disproportionately by agencies already prepared to embrace the technology, so as their NDC volumes grew, the aggregate share rose quickly. The next stage looks different: as more agencies establish NDC connectivity, the incremental participants are not necessarily moving large portions of their business through NDC right away. They may have the connection and the operational capability to support it while still routing most transactions through established channels.
That creates an important distinction between breadth of adoption and depth of adoption. Breadth is expanding, with more agencies doing NDC business. Depth is moving more slowly, with the overall share of transactions attributed to NDC holding near 21% despite that wider participation. This does not necessarily indicate declining interest in NDC, nor does it prove adoption has reached a structural ceiling. It more likely reflects the mechanics of moving from an early-adopter market into a much larger population of agencies where adoption begins with small volumes and builds from there.
For airlines, aggregators and technology providers, that distinction matters. A transaction-share chart read in isolation makes the market look stagnant. The agency participation data tells a more useful story: the market is still expanding in terms of who is engaging with NDC, even though that expansion has not yet produced proportional growth in NDC’s share of overall volume.
The pattern that matters here is not the 21.5% figure itself but what it sits next to. Connectivity is outrunning volume migration, which means getting agencies connected was the easier half of NDC adoption in the U.S. market. Turning that connectivity into sustained transaction share is the harder second step, and August’s data shows the industry is still in the middle of it.
