NDC Development
NDC API Integration Guide for Travel Developers
A technical walkthrough of NDC API flows — from AirShopping to OrderCreate and post-booking servicing
By Project OTA | 8 Aug, 2026 | 8 min read
NDC integration requires managing offer shopping, order creation and post-booking servicing through XML API flows that differ by airline. This guide covers the core NDC messages and integration patterns.
Core NDC message flows
The NDC standard defines a set of XML request-response message pairs that cover the full booking lifecycle. AirShopping is the search request — it returns Offers containing fare families, prices, ancillary options and seat availability. OfferPrice reprices a selected offer immediately before booking to confirm the current price. OrderCreate creates the booking, confirms the offer and initiates payment. OrderRetrieve fetches order details. OrderChange handles modifications and OrderCancel handles cancellations.
In practice, not all airlines implement all messages. Some airlines implement only AirShopping and OrderCreate, leaving post-booking servicing through a separate API or manual process. Developers must handle partial NDC implementations gracefully and plan fallback paths for airlines with limited NDC coverage.
Authentication and connectivity
Each airline manages NDC access independently. Most require registration as a technology partner or aggregator, followed by credential issuance, API endpoint documentation and sometimes a certification process. Authentication varies: some airlines use OAuth2, others use API key headers, and some still use certificate-based authentication tied to the agency's IATA or TIDS number.
NDC aggregators — such as Verteil, Duffel, Travelfusion or Farelogix — solve connectivity by providing normalised NDC access to multiple airlines through a single API integration. Using an aggregator reduces the time to connect to multiple airlines but introduces a dependency and potentially limits access to airline-exclusive offers.
Normalising NDC with GDS content
The most common architectural challenge in NDC integration is normalisation. GDS search results arrive in EDIFACT or proprietary REST formats with specific field structures. NDC results arrive in airline-specific XML with different offer models, ancillary packaging and pricing logic. A booking engine that wants to show combined results must map both to an internal canonical model.
The canonical model should store enough supplier-specific detail to route the booking correctly: GDS PCC and provider reference for GDS bookings, airline NDC order ID and API endpoint for NDC orders. Servicing requests must know which channel originated the booking to send change or cancel requests to the correct API.
Testing and certification
Most airlines provide a sandbox environment for NDC API testing. Sandbox credentials differ from production and the test content may not reflect live fares or schedules. Regression testing for NDC integrations is important because airlines update their API schemas and offer structures regularly — a schema change upstream can break the booking flow downstream if the integration layer is not resilient.
Before production launch, verify AirShopping results match airline website prices, confirm OrderCreate successfully creates a bookable order, test payment flows and validate that order management messages return correct responses. Track API response times and build retry logic for transient failures.
Frequently Asked Questions
Is NDC hard to integrate compared to GDS?
NDC is more complex per airline because each implementation differs. GDS provides one consistent interface for many airlines. NDC requires either individual airline integrations or connecting through an NDC aggregator.
What airlines support NDC?
Most major carriers now have NDC programmes including British Airways, Lufthansa Group, Air France-KLM, Emirates, American Airlines, Qatar Airways and others. Coverage and depth vary significantly.
Can NDC handle interline and codeshare itineraries?
NDC is primarily designed for single-airline offers. Multi-airline interline itineraries that require prorate agreements and cross-airline servicing are still handled more efficiently through GDS.
Key Takeaways
- NDC uses XML message flows: AirShopping, OfferPrice, SeatAvailability, OrderCreate.
- Every airline's NDC implementation differs — normalisation is essential.
- Post-booking servicing (change, cancel, refund) requires order management flows.
Project OTA builds NDC-ready booking engines with normalised GDS and NDC content, order management and full post-booking servicing workflows.
Talk to Project OTA