Amadeus vs Galileo: GDS Comparison
6 min read
A global distribution system, or GDS, is the computerised reservation platform that connects travel agents to airline inventory, hotel beds, car hire, and rail in real time. When an agent books a flight, the request travels through a GDS to the airline's inventory system, the seat is allocated, and a PNR is created. Two GDS platforms dominate the agency market: Amadeus, headquartered in Madrid, and Galileo, now part of Travelport, which also operates the Apollo system used primarily in North America. Despite serving the same fundamental purpose, the two systems have different origins, different geographic strengths, and meaningfully different display conventions that affect how you read the output they produce.
A short history of each system
Amadeus was founded in 1987 by four European airlines — Air France, Iberia, Lufthansa, and Scandinavian Airlines — as a jointly owned neutral GDS. It launched commercially in 1992 and expanded rapidly across Europe, then into Asia-Pacific and Latin America. Today Amadeus IT Group is a publicly listed company trading on the Madrid stock exchange. It serves airlines directly through its departure-control and reservations systems as well as travel agencies through the Amadeus terminal. Because of its European roots, Amadeus is particularly dominant among agencies in Western Europe, Scandinavia, the Middle East, and much of Asia-Pacific.
Galileo was founded in 1971 as part of United Airlines' internal reservation system, later becoming the Covia partnership and then Galileo International after merging with several European airline reservation networks in the early 1990s. Apollo, a parallel system developed from the same United Airlines heritage, remained the primary GDS for North American agencies. Both Galileo and Apollo were subsequently acquired by Cendant, then spun off as Travelport in 2006. Travelport now operates both platforms — Galileo in Europe, Asia, and the Middle East, and Apollo in North America — under a single corporate structure.
Side-by-side comparison
| Attribute | Amadeus | Galileo (Travelport) |
|---|---|---|
| Owner | Amadeus IT Group (publicly listed) | Travelport (private equity backed) |
| Origin | Founded 1987 by European airline consortium | Derived from United Airlines Apollo system, 1971 |
| Primary regions | Europe, Middle East, Asia-Pacific, Latin America | North America (Apollo), Europe, Middle East, Asia |
| Command style | Cryptic one-line commands; entry prefixes like RT, SS, TT | Cryptic commands with different prefix conventions; GT, A, B entries |
| Time format | 24-hour (e.g. 0240, 1430) | 12-hour with AM/PM suffix (e.g. 0240A, 0230P) |
| Segment status | HK, HL, TK, UN — same two-letter codes as Galileo | Same two-letter codes; minor display layout differences |
| Display feel | Segment lines lead with element number, then carrier and class | Segment lines lead with segment dot-number, party reference first |
| Common in | European agencies, Middle East carriers, many Asian markets | North American agencies, some European and Asian markets |
Which system will you encounter?
The GDS your agency uses depends primarily on geography, the agency's historical contracts, and the host airline relationships it has. European full-service agencies opened before the early 2000s are more often on Amadeus; North American agencies more often on Apollo or Galileo. Middle Eastern agencies split between the two, with a number of Gulf carriers having particularly close integrations with Amadeus.
From a passenger or reader perspective, the GDS distinction rarely matters for the content of the booking — the same airlines, fares, and seat inventory are available through both systems. What changes is the format of the output. When a traveller forwards you a raw PNR or itinerary printout from their agent, you may receive either format. Some clues to look for: if the time fields end in A or P, you are reading Galileo output. If times are purely numeric in 24-hour format and the header line starts with RP/, you are reading Amadeus. Carrier-issued itineraries formatted by the airline's own system may differ from either.
Reading output from either system
Both Amadeus and Galileo pack all the essential segment information — carrier, flight number, booking class, route, status, and times — into a single line. The fields are in a similar order in both systems, but the conventions for times and day offsets differ enough to cause confusion if you assume one system's format while reading the other's.
In Amadeus, times are in 24-hour format (0240 for 02:40, 1430 for 14:30), and arrival-day offsets are not always shown inline on the segment. In Galileo, times carry an AM/PM suffix (0240A for 02:40 AM, 0900P for 21:00) and overnight arrivals carry a +1 or +2 marker directly after the arrival time. The status codes — HK for confirmed, TK for schedule change, UN for unable — are shared across both systems, as they derive from a common IATA airline reservation standard. For a full walkthrough of how to read each format, see the dedicated reading guides linked below.
For agents who work across both systems, the most reliable approach is to paste any raw GDS output into a formatting tool rather than reading it raw. Automated formatters can detect the display convention, convert times to a consistent format, and flag day offsets — eliminating the risk of misreading a departure time and booking a passenger for the wrong flight.
FlyTix automatically detects whether a pasted segment display comes from Amadeus or Galileo — you do not need to identify the source system before formatting.