Once a passenger is through-checked, that passenger is provided protection in the event of a flight disruption, even if the passenger has chosen to purchase separate tickets.

If you have been provided a connecting boarding pass – regardless of any baggage – the oneworld carriers will provide protection for you in the event of a flight disruption.

If you are attempting to combine three tickets (three separate airlines) into a single itinerary, through check-in will fail for the third segment. Today’s airline systems generally do not support interline through check-in for a third (or more) airline in the itinerary, whether on a single tickett [sic] (and in a single booking record) or not. If these are three oneworld member airlines, then, yes, with today’s policy our members should treat this as a single itinerary regardless of the through check-in. However, the airlines may not have information about your full itinerary in order to create the most convenient protection for you. A single booking record (and a single ticket) will provide more protection in spite of our best intention with your separate tickets.

oneworld has chosen not to publicly highlight (on our website or other communication channels) our policy of through service provided for separate tickets. Traveling on separate tickets for a single itinerary can compromise our member airlines’ (or any two airlines) ability to provide proper through service for our customers, even where there are just two airlines in the itinerary. For example, our ability to provide through check-in service can be compromised if passenger names are not entered in exactly the same way during the two separate booking processes

As an alliance, we are reviewing this policy. One concern, for example, is that without adequate fare information for the downline segment the originating carrier cannot properly assess bag charges while regulators have specific requirements regarding baggage charges on single itineraries. In this case, carriers face a potential obligation for which they do not have the information to meet that obligation. There are other factors which airlines will individually review, including economic concerns of providing expensive services and disruption liability for which the traveler has chosen not to pay.

Our members confirm that they have trained their agents according to this policy. While we do not list this information on oneworld.com, many of our individual members clarify this policy on their own websites.

I don’t believe you should encounter a situation where one of our members or an individual agent chooses to ignore known/understood policy for commercial reasons.

When you check-in, advise the agent* of your actual final destination (the agent will not otherwise have this information) and show the agent details of your reservation with a oneworld member airline. The agent should attempt to generate a connecting boarding pass (which will usually be successful) and will check bags to final destination (which should always be successful - subject of course to the need to reclaim bags at an interim point for customs clearance, for example, upon entering the U.S. with continuing domestic U.S. travel).

For protection from policy failures – you could bring with you a printout from the member airline webpage (for example, the aa.com page listed below). I don’t believe you should encounter a situation where one of our members or an individual agent chooses to ignore known/understood policy for commercial reasons.

For protection from technology failures – those “conflicting reports” may indeed reflect technology failures to complete through check-in messages. While an agent can generally create a through check-in with separate tickets, itineraries built as a single itinerary issued on a single ticket will have a higher success rate for through check-in than itineraries constructed through separate reservations processes. I don’t have any secrets to share which would improve upon this success rate other than purchasing a single ticket for a multi-segment itinerary.

The passenger contract is with the airline, in the form of the ticket. Once a member has checked you to final destination, each member in that through itinerary is obligated to provide full service including, for example, protection in the case of disruption. If you encounter a problem with one of our members applying this policy, you would need to pursue any concerns with that airline.

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* The requirement to use an agent at check-in is another concern being reviewed by our members regarding this policy. In every travel market, airlines including oneworld members are attempting to facilitate movement through the airport with increased self-service opportunities. For example, print-at-home bagtags will soon become as common as print-at-home (or mobile) boarding passes – but these clearly will not work when the originating airline does not have the full travel details.