IATA NDC

NDC is the standard the air industry built to change who controls the sell. Adopted by IATA resolution in 2012, it replaces the fare-and-availability model that EDIFACT and the GDS layer implement with an offer and order model: the airline constructs the offer, owns the order, and any seller with access can transact against it. Schema releases are named by year — 17.2, 18.2, 21.3, 24.1 — and the EDIST namespace carries the version explicitly.

• Offer and order, not fare and availability - AirShopping, OfferPrice, OrderCreate and OrderChange replace the shared inventory model. The airline is the source of truth for what is for sale and at what price.
• Certified in levels - IATA runs conformance certification, and the levels are not equivalent. Level 4 claims full offer and order management; NDC@Scale is a separate volume-based programme.
• XML, and versioned by release year - implementations pin a schema version, and two airlines on different releases are not automatically interoperable.
• The OrderID is minted by the platform - which matters more than it looks. See below.

What the evidence shows

Across the four State of Travel APIs Sector Reports, NDC is the most-cited standard in the sector and the least reachable. Certification, publication and a working endpoint turn out to be three separate things, and providers routinely hold one or two without the third.

The State of Australian Travel APIs records the clearest case of a standard converted into a pricing instrument. Qantas is NDC@Scale certified. GDS bookings carry A$11.50 per segment on EDIFACT and A$4.50 on Standard NDC, while the Qantas Distribution Platform portal, Certified Technology Partners and an invitation-only Premium NDC tier carry no surcharge at all. The interoperability standard was adopted and immediately became a channel-pricing ladder. In the same market, Flight Centre holds IATA NDC Level 4 certification — its own claim is to have been the first global TMC to reach full offer and order management — and scores 15.6, barely above the Minimal line, with no public NDC endpoint, no published NDC API, and /terms, /terms-of-use and /legal all returning 404.

The State of Canadian Travel APIs shows three airlines producing three different outcomes from the same specification. Air Canada publishes NDC 17.2 (EDIST) properly and fully, then makes production access contingent on certification, application audit, unilateral thirty-day changes to display obligations, and revocation at sole discretion. WestJet has held NDC Certification Level 2 since March 2017 and has Direct Connect built in 17.2 and 21.3/24.1 — not yet live, with rollout stated for Q4 2026, while a US$20–22 surcharge on non-NDC EDIFACT bookings is already in force. The surcharge for not using the new channel arrived nine years before the channel. Transat publishes an NDC programme page in both official languages and ships a proprietary Radixx SOAP API underneath.

The identifier finding is the one worth carrying forward. NDC introduces a platform-minted OrderID, along with OfferID and OfferItemID. The portable keys in travel are the ones IATA owns — airline and airport designators, PNR record locators, agency accreditation numbers, PADIS code lists, EMD documents. By making the primary booking record hang on an airline-minted identifier, NDC moved the record key from the portable column into the vendor column. A standard designed to reduce switching cost increased it at the identifier layer — the first instance of that pattern this research programme has recorded, and the reason the Kin Score roadmap now carries a standalone Switchability lens.

Compare OpenTravel, whose volunteer non-profit publishes royalty-free machine-readable code lists, a compiler CLI and an MCP server, and scores 55.1 — against IATA, which authors NDC and scores 21.5.