Travel Explained
What Is a Codeshare Flight?
Learn why one airline may sell a flight operated by another carrier, how to identify a codeshare, and which airline’s rules apply during your trip.
Flights, Tickets & Airline Rules • Travel Explained
The Quick Answer
A codeshare flight is a flight sold under the names and flight numbers of two or more airlines but physically operated by only one carrier. This allows partner airlines to sell seats on the same aircraft and offer passengers access to destinations beyond their individual networks.
Your confirmation should identify the operating airline with wording such as “operated by.” That airline provides the aircraft and crew, and its baggage, check-in, seating, and onboard procedures may apply even when you purchased the ticket from another carrier.
How Codeshare Flights Work and Which Airline Operates Your Trip
A codeshare is a marketing arrangement in which one airline places its flight code on a service operated by another airline. The U.S. Department of Transportation’s codeshare guidance explains that airlines use these agreements to sell partner-operated flights and expand the destinations available through their networks.
For example, you might purchase a ticket from Airline A and receive an Airline A flight number, but Airline B provides the aircraft, pilots, cabin crew, and onboard service. Airline A is the marketing carrier, while Airline B is the operating carrier. Several airlines may sell seats on the same physical flight using different flight numbers.
Airlines and ticket sellers in the United States must disclose the actual operating carrier. Under the federal codeshare notice requirements, written confirmation must identify which airline operates the flight. Look for wording such as “operated by” beneath the flight number before completing the purchase.
The operating airline matters because it determines the aircraft, cabin layout, seat, check-in deadline, onboard service, and many airport procedures. Even if you purchased the ticket through another airline, you may need to check in with the carrier operating your first flight. American Airlines, for example, advises passengers traveling with its partners to check in with the airline operating the first segment.
Baggage rules can be more complicated. For itineraries beginning or ending in the United States, federal policy generally requires the applicable baggage allowance and fees established at the beginning of the itinerary to remain consistent throughout qualifying codeshare journeys. However, restrictions for carry-ons, special equipment, seat selection, or optional services can still differ between the marketing and operating airlines.
Codeshares can make international and connecting trips easier to purchase as one itinerary, but do not assume every benefit transfers between partners. Before booking, identify the operating airline for every segment and check its aircraft, seat map, baggage rules, check-in location, lounge eligibility, accessibility procedures, and frequent-flyer earning rules.
Travel Explained in Practice
Imagine This…
You purchase an international flight directly from an airline you recognize. When you reach the airport, however, the departure board lists a different carrier beside your destination. Your confirmation says “operated by” that second airline, meaning it supplies the aircraft, crew, check-in procedures, and onboard experience even though another carrier sold you the ticket.
Know the Airlines
Who Does What on a Codeshare Flight?
The marketing airline sells the flight under its code, while the operating airline physically performs the journey.
Marketing Airline
This is the carrier whose flight number appears during the search and which sells or markets the partner-operated flight.
Operating Airline
This carrier supplies the aircraft, pilots, cabin crew, onboard service, and many of the day-of-travel procedures.
The Traveler
You should identify both carriers and check which airline handles check-in, baggage, seats, accessibility, and flight changes.
The Operator Matters
The Airline Selling the Ticket May Not Operate the Flight
The operating airline determines the aircraft and physical travel experience, even when the flight carries another airline’s code.
Sold By
The Marketing Carrier
Its code and flight number may appear prominently in your search results, reservation, and ticket.
Operated By
The Airline You Actually Fly
Its aircraft, cabin, seating, crew, meals, accessibility procedures, and onboard policies shape the flight.
Before You Fly
Five Things to Check on a Codeshare Itinerary
Find the “operated by” label.
Check the operating carrier for every segment before purchasing the itinerary.
Confirm where to check in.
You may need to use the website, app, or airport counter of the airline operating your first flight.
Review the baggage rules.
Check allowances, fees, carry-on dimensions, special-item policies, and whether luggage will transfer.
Check the aircraft and seat.
The operating airline’s cabin may differ from the product you associate with the marketing carrier.
Verify partner benefits.
Seat selection, lounge access, upgrades, mileage earnings, and elite benefits may not transfer automatically.
Travel Explained Note
Did You Know?
The same physical flight can appear under several airline codes and flight numbers. Regardless of which carrier sold your ticket, every passenger is ultimately traveling on the aircraft supplied by the operating airline.
Quick Review
Key Takeaways
A codeshare has more than one airline code.
Several partner airlines may sell seats on the same physical flight.
The operating airline provides the aircraft and crew.
Its cabin, seating, service, and many day-of-travel procedures determine your experience.
The operator must be disclosed.
Look for “operated by” during the search and on your ticket confirmation.
Partner benefits are not always identical.
Verify baggage, seats, lounge access, upgrades, mileage earnings, and check-in procedures.
Common Questions
Frequently Asked Questions
Which airline do you check in with for a codeshare flight?
You will often check in with the airline operating your first flight. Review your confirmation and the operating carrier’s instructions before arriving.
Which airline’s plane will you fly?
The operating airline provides the aircraft and crew. Look for the “operated by” label to identify it.
Which baggage rules apply to a codeshare flight?
The answer depends on the itinerary and applicable regulations. Review the baggage information on your confirmation and check both carriers’ rules for optional and special services.
Why do airlines use codeshares?
Codeshares allow airlines to sell partner-operated flights and offer passengers access to destinations beyond their own individual networks.
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