Minneapolis-St. Paul International Airport

Long before the current American Airlines campaign to shake up the data distribution system, airline agents often refused to change tickets issued by travel agencies and third-party websites, such as Expedia and Orbitz. Dealing with those companies’ agents can be frustrating, and many fliers call the airlines for help directly, only to be sent back to the “original booking source.” Why?

Because once the airline takes control of the ticket, it effectively releases the original booking source from its responsibilities as the issuing agent — and when the booking source loses control of the ticket, it will no longer keep track of your reservation.

So if there is a schedule change, that source won’t alert you, because it won’t know itself that a change has affected you. In other words, the link between the booking source and the airline will be broken, and the source won’t act as your agent. Instead, the airline will have to assume responsibility not only for notifying you of any changes, but also for rebooking you and reissuing your ticket.

Airlines don’t want that responsibility. The reasoning they offer customers usually is that the issuing agency may not have transmitted the passenger’s correct and full contact information, and they don’t want to be blamed in case you weren’t informed of any changes. That can be easily taken care of when the customer calls to voluntarily change a ticket, but there is a more serious reason, which airline agents almost never mention.

It comes down to money. Here is the airlines’ argument: They will be happy to keep track of your reservation, notify you of schedule changes (whether they actually do is another issue), rebook you and make any other changes, if the particular fare allows them. But if this is what you want, you should book your ticket directly with them. They pay web travel agencies to display their flights. If you booked your Delta ticket on Orbitz, why should Delta, which is paying Orbitz, have to bear the labor and other costs of changing your ticket?

Now, Delta will charge you the $150 or $250 change fee either way, depending on your fare rules, but that’s a different issue. This is about spending the time of a reservations agent — and possibly other airline employees. Delta prefers to use those employees’ time and effort to help direct Delta customers, not those booking through a middleman.

So don’t be surprised if an airline agent declines to deal with your reservation and sends you back to Travelocity or Priceline — or wherever you booked your ticket. That other agent may not be as well-trained as an airline employee and may have a limited capacity to help you, but you should think about that before you buy a ticket.

When might an airline agent agree to help you? Most likely, after travel has begun or if you are affected by severe weather and the airline has issued a change-fee waiver. Some agents may take mercy on you if you’ve been battling in vain with an online agency’s outsourced customer-service representatives in India or other overseas locations. It’s fashionable to pick on India, but did you know that Expedia has an English-speaking call center in Egypt?

As with any exceptions you want made for you, your chances of succeeding are much higher if you are an elite member of the airline’s loyalty program. Just ask politely — not as if you are entitled — and ensure the agent that you understand it’s your responsibility to check your reservation’s status from time for time and stay informed about any schedule or other changes.

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