Navigate the murky waters of airline partnerships, part 1

Discover the new world of airline alliances

On your next trip, it’s possible that you’ll book your ticket on Continental, have one of your flight legs operated by Delta, and choose to earn frequent flyer miles on Northwest, all so you can get an award seat on a KLM flight next year. Confused yet? A series of new airline alliances within the past year makes this scenario perfectly possible, but it has also left a lot of flyers wondering how these partnerships work, and whether their travel experience will improve as a result.

Worry no more. We’ve found the answers to the most commonly asked questions about airline alliances and “codeshare” travel, when one carrier sells seats on another’s flights. Whether you want to know how to book an award seat on US Airways with United miles, or if the new KLM-Air France merger will increase or reduce the cost of flights to Europe, you’ll find that once you learn about airline alliances, you’ll understand how they can save you money while improving your flight experience.

In the first part of this series, we answer some of the most common questions about navigating the often confusing world of airline alliances.

The ins and outs of flying allied airlines

Booking a ticket, checking in, and earning miles can all seem more baffling when you’re talking to one airline and flying on another. Read on to find out who’s partnering with whom, and how you can confidently book and travel on a codeshare ticket with no confusion about where to go and who to contact.

Which airlines are partners?

More airline partners: For a list of all of your preferred airline’s partners, check our Mile Finder.

Each of the major U.S. airlines has many partners, but there are some key alliances that all travelers should be aware of. Domestically, United and US Airways have had a working relationship for the past year, and Continental, Delta, and Northwest have recently partnered up in a three-way agreement. In the international arena, the three biggest alliance groups are Star Alliance, headed by United, Air Canada, and Lufthansa; SkyTeam, helmed by Delta and Air France; and oneworld, led by American and British Airways. Meanwhile, Northwest and KLM have had a longstanding partnership, and [% 5607 | deal | KLM and Air France %] recently announced that they will be merging under a parent company, while retaining their individual brands.

What is codesharing, and how is it different from an alliance?

While the terms are sometimes used interchangeably, codesharing is one of the benefits of airline alliances. Codesharing is the practice of one airline putting its two-letter code (e.g., NW for Northwest, US for US Airways) on a flight operated by another airline. The first airline can market and sell seats on that flight, even though its planes are not operating on that route. These agreements give airlines the ability to sell tickets to more destinations, while the benefit for travelers is that they can fly a multiple-leg trip as if they were using a single carrier, when in fact they may be taking two or more airlines’ planes.

How do I book tickets with partner airlines?

You can still book tickets through your preferred airline if you’re traveling on one of its partner’s flights. Through the codeshare, each airline has access to a certain number of its partner’s routes, and has license to sell tickets on those flights. For instance, you can call Delta to make a reservation, but end up booking a seat on a Northwest or Continental plane. The flight will still have a Delta flight number associated with it.

And because of codesharing agreements, it might be possible for the same seat to be available through one airline and not another. For example, a flight between Cleveland and Chicago operated by Continental might not have any available space if you try to book with Continental, but a call to Northwest could reveal empty seats on the same flight, marked with that airline’s code and flight number.

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In cases such as this one, if you’re looking for a seat on a specific flight, it’s a good idea to check with each of the partner airlines. And because the fares may be different depending on which airline you book with, it pays to shop around.

How do I know which airline I’m actually flying, and where do I check in?

The flight number should tell you which airline you’re traveling with. For example, US Airways flights numbered 6000-8299 are United-operated flights, while United flights 1700-4589 are US Airways-operated flights. You can check with your airline by phone or on their website to learn which flight numbers signify codeshares, if it’s not specified in your reservation.

When you arrive at the airport, you should check in with the carrier operating your first flight, regardless of which airline you contacted to book your ticket (i.e. the carrier whose two-letter code is on your flight number). You can use self-service kiosks or the website of your originating airline to check in, even if you did not book your ticket directly with that airline. If your journey involves flights on more than one airline, you only need to check in once. You’ll be able to get all of your boarding passes simultaneously, and check your luggage through to your final destination.

Who do I talk to in case of a problem?

If you have difficulty with your reservation prior to your flight, it’s best to contact the airline with which you booked your ticket, though representatives of either carrier should be able to help you. Once at the airport, you should direct questions relating to your flight, such as problems with check-in or seat assignments, to your originating carrier. Questions about baggage loss or damage can be asked of either airline, though it’s probably best to speak with the airline you flew to your final destination. Don’t worry about contacting the wrong airline, because each airline should be able to direct you to the person who can best help you.

How do I earn and redeem frequent flyer miles with partner airlines?

You can earn frequent flyer miles for your preferred airline on any of its partners. You will need to make sure that your member number is attached to your itinerary, by providing it when you make reservations or at check-in. Unless stated otherwise, bonus miles are only available in the mileage currency of the airline operating the flight. For example, you can’t earn extra Northwest miles, besides what you normally earn for the flight, when you travel on a Continental plane. If Continental were offering a promotion on that route, it might make more sense for you to earn Continental miles, instead of Northwest miles, on that trip, so you’ll be able to take advantage of the bonus. Remember that miles earned on a partner flight often take longer to post than regular miles, but they should post within six to eight weeks of your flight.

Even though you’re booking with one carrier and flying another, every airline has separate frequent flyer accounts. So while you can earn miles on a partner flight, you cannot combine your frequent flyer miles from different airlines into one account without paying the typical [% 5540 | deal | conversion costs %].

You can also redeem miles for flights on any of an airline’s alliance partners. When you call or log on to request an award, you should be able to see all of the possible partner options. This can be helpful even when you’re trying to book an award ticket on your preferred airline; if there are no seats available on the date you want, be sure to ask if there’s a seat on one of its partner’s flights.

For more complicated trips, award tickets can sometimes combine two or more alliance airlines for one price; the amount of miles you need will depend on your preferred carrier’s award levels.

How do I upgrade my ticket on a partner airline?

Upgrades are a trickier business. Many airlines do not let you use miles to upgrade on a flight operated by a partner carrier. For instance, you cannot use US Airways miles to upgrade a United flight, although you can purchase upgrades for cash on the date of travel; with a few exceptions, the Star Alliance airlines do not allow upgrades on other airlines. You can use Northwest miles to upgrade Continental or KLM flights, and vice versa; however, you cannot upgrade Delta flights. So while in most cases you won’t be able to use another airline’s miles to upgrade, you should always check with the carrier you’re flying to be sure.

In the next installment of this article, we’ll show you why industry experts think alliances are a win-win proposition for both airlines and travelers. Stay tuned for the second half of “everything you always wanted to know about partners in the sky.”