Travel Glossary · Air Travel
Codeshare
Definition
Codeshare: A codeshare is an agreement in which one airline sells seats under its own flight number on a flight operated by a partner airline.
Codeshares let airlines extend their networks without flying every route themselves. A single flight can carry several flight numbers from different airlines, but only one airline actually operates it. Your itinerary will say “operated by” followed by the operating carrier, and that is the airline whose aircraft, crew, and onboard product you will experience.
That detail matters. You usually check in with the operating airline, its seat maps and cabin product apply, and baggage rules, seat selection, and upgrade eligibility can differ from what the marketing airline offers on its own flights. Codeshares are especially common within airline alliances and joint ventures, which our airline alliances guide explains.
When we compare options, we look at who operates each flight, not just whose code is on the ticket, especially in premium cabins where seats vary widely between partners.
Example: A flight sold with a Delta flight number between the US and Paris may be operated by Air France, so you check in with Air France and fly on its aircraft.
Go deeper
- Travel GuidesAirline Alliances Explained: Star Alliance, oneworld, and SkyTeamAirline alliances explained: who belongs to Star Alliance, oneworld, and SkyTeam, how elite status and lounge access work across partners, and how to use them.
- Travel GuidesHow to Choose a Business-Class Seat on Long-Haul FlightsHow to choose a business-class seat: check the aircraft, understand 1-2-1 and suite layouts, pick the right seat for solo or couple travel, and avoid bad rows.
- Corporate TravelBusiness Flight Booking for Companies and ExecutivesBusiness flight booking from a Los Angeles corporate travel advisor: smarter fares, tracked ticket credits, and one person handling every change.
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