Which luggage rules & charges apply on codeshare flights?

[D4]

I want to book a flight from Chicago to Seville, Spain (connecting through Madrid.)

 

The flights I'm considering are codeshare flights and the exact same flights have significantly different prices based on which airline I book it under (Iberia, British Airways, American.)

 

On a codeshare flight, which airline's baggage rules and charges apply? The airline I book it under or the airline whose metal is flying?

 

Thanks!

[Gonzo70]

The airline actually operating the flight is the one who's rules rule - not the airline you purchased the ticket through.

[frugaltravel]

To clarify, it is the rules of the airline that is the "most significant carrier" in the itinerary. It sounds like you have a non-stop flight from Chicago to Madrid so the airline that operates that flight would be the one whose rules you follow.

 

If someone were first connecting on a shorter flight within the USA to the longer transatlantic flight, they would use the rules of the airline that operates the transatlantic flight.

[slidergirl]

I have my own personal rule: use the most restrictive rules of any of the airlines I'm flying on a trip. Works every time ;)

[D4]

Thanks for the responses