OSDM — Open Sales and Distribution Model

Scope

OSDM (Open Sales and Distribution Model) is a UIC-coordinated, open-source REST/YAML specification for public transport ticket distribution, designed to let retailers, distributors and carriers exchange fares, offers, reservations and after-sales transactions through a common interoperable API instead of bespoke bilateral interfaces. It targets both a Retailer mode (selling admissions, reservations and ancillaries) and a Distributor mode (also combining fares from multiple carriers into priced offers).

The OSDM specification covers an Offline Data Model (fares, products, code lists) and an Online API split into Retailer and Distributor modes, with common data structures for offers, reservations, place management, after-sales processes (refunds, exchanges, compensation) and account-based ticketing. It is published as OpenAPI/YAML definitions with Swagger and Redoc renderings for every release; the current stable release is v3.9.0, with v4.0.0 published as a draft, and the full version history back to v2.0.7 remains published for implementers on older lines. OSDM grew out of the international rail-ticketing community coordinated by UIC and has since drawn in distributors, retailers and mobility platforms beyond rail; it complements Transmodel-family formats (NeTEx, SIRI) by addressing the commercial/distribution layer those do not cover, and is increasingly cited alongside the TAP TSI (now merged into the TEL TSI) as an alternative or complementary interoperable-ticketing mechanism for cross-border and multimodal sales. The specification, its UML model, sandboxes and reference implementations are open source and freely available; used by railway undertakings, distributors, mobility-as-a-service platforms and ticketing-system vendors building interoperable retail interfaces.