Why interline agreements should matter to you

The travel industry is full of jargon. Airline-travel agency terms often seem meaningless to travelers, like “interline agreements.”

interline agreements“Interline agreement,” is anything but meaningless. Sadly, many people have discovered this fact of flying during the 2022 holiday season. Not only with international flights but with domestic flights, the jargon has importance.

The term “interline agreement” can refer to an airline being able to sell a ticket with multiple carriers involved and be able to check luggage between those airlines. Now, that doesn’t happen that much these days. It’s more common on international tickets in the case of code-shares or airline partnerships, for example, United and Lufthansa, or Delta, KLM, and Air France.

Once upon a time, domestic interline agreements were also used extensively for domestic routes. Today they are much rarer.

There are infrequent cases within the US. For example, American and Alaska Airlines sometimes sell connecting domestic flights on each other’s aircraft. But in general, especially on flights within the US, flights from different airlines are generally put on separate tickets with separate fares.

From a traveler perspective, these codeshares are a mixed bag. In case of problems, it’s more seamless to have one ticket, but it can be confusing. Most travel agents have plenty of stories on blame games with luggage or missed connections when clients are flying on codeshare tickets.

Some codesharing is helpful for passengers when flights are canceled.

Irritated by hotel resort fees?Airlines have the ability to put passengers on airlines with whom they have interline agreements. They don’t LIKE to do it, since it means giving the revenue to a competitor, But if asked and sometimes pushed by travelers or travel agents, airline ticketing staff will agree. It’s worth something in goodwill and not having an angry passenger stuck at an airport.

Plus, airlines know airport problems happen to all of them and usually at different times. I once had travelers with tickets on connecting flights from Washington National Airport to Los Angeles. A freak ice storm shut down Charlotte airport, where he was connecting. I talked American into putting him and his wife on a United connection via Chicago. He was incredulous they would do it. But, next time, it might have been O’Hare with the issue, and maybe United would need American Airlines’ help.

Southwest has no interline agreements with other airlines.

The reason interline agreements matter came into focus this week. Southwest Airlines doesn’t have them. (For that matter, neither do many, if not most, smaller discount carriers have these interline agreements. Frontier Airlines and Allegiant are other notable cases.)

Join UsAnd there’s not a lot of give in the aviation system around holidays and during storms. But when a carrier can’t even have the ability to transfer a ticket (or endorse it) to another airline, it can become a bigger problem.

Southwest’s problems were bigger than not having interline agreements. The fact that the airline couldn’t put stranded passengers on another airline made it worse.

Other airlines have few interline agreements. Either it is their choice or the decision of other carriers.

Some travelers on other carriers also had a rough holiday over interline agreements or lack thereof. A friend booked his daughter on Spirit Airlines and she had a flight canceled. While there were flights available on other airlines, she was told she had to wait until there was space on Spirit Airlines.

Now, admittedly many carriers without interline agreements are considered “discount carriers,” and there is the sense that “you get what you pay for.” Many legacy carriers have stopped interline agreements with other network and discount carriers. The larger airlines believe that having multiple departures is a competitive advantage.

But, while Southwest doesn’t charge for checked baggage, it is often not the least expensive. And travelers may decide to save money by giving up perceived frills. However, getting to a destination is not generally considered a frill. So, when Southwest has a problem, it is a big one. They are the largest airline at most airports and have plenty of flights. Passengers believe that airlines should get passengers from Point A to Point B.

Now, even being on a legacy carrier is no guarantee that an airline will solve any problem. A flight delay problem can happen at any time. Often, weather affects everything in and out of an airport and sometimes every alternative flight is full. Also, you or your travel arranger may have to fight hard for one airline to put you on an alternative airline flight.

As mentioned, airlines prefer to keep you on their planes so they keep the money you paid for the ticket. But being on an airline with interline agreements will give you a better chance with more options. And these days, travelers need all the options they can get.

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