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Fly Safe, Fly Smart: How to Decode Code Shares

Code shares are lies the airline industry tells to make their lives easier. They take one airline's flight and stamp another airline's name on it. Here's what's wrong and what's right with the practice.

One day I booked a Delta flight to San Diego, with a change of planes in L.A. So far, so good. But in L.A. I found myself whisked out of the Delta terminal to a distant, satellite terminal and put on a plane flown by "American Eagle," who temporarily lost my luggage because their facilities were so far from Delta's.

Welcome to the world of code shares.

Code shares are lies the airline industry tells to make their lives easier. They take one airline's flight and stamp another airline's name on it. This allows American, for instance, to say they fly to Budapest when they don't. Malev Hungarian flies to Budapest. American sells some tickets on that flight under their own name. But you're flying Malev, my friend.

Here in the U.S., most domestic codeshares have to do with larger airlines subcontracting flights to smaller regional airlines. These regionals could be wholly-owned by the majors but designed to avoid labor agreements, like American Eagle and Comair, or independent airlines like Trans States.

Globally, most large airlines are arranged into three "alliances," groups that agree to share frequent-flier miles and sell tickets on each others' planes. Often these airlines are proud, world-class entities, but that doesn't help when you show up at the wrong airport terminal for check-in or are looking for a nonexistent "American Airlines" counter at an airport in Hungary that doesn't have one.

How To Find Code Shares -- And What To Do About Them

The words "operated by" are your code share red flag. When you're shopping for flights, you'll find this poisonous little phrase in small type, usually under the flight number in a website's listings. If you're shopping on an airline's website, they may just indicate it with an asterisk next to the flight number.

"Operated by" means "not your airline."

Other signs are when two airlines' flights to the same destination leave at the exact same time. They're usually the same flight, divvied up as a code share.

If you're flying on a code share (and yes, there are reasons to do it -- see below) pay attention to that "operated by." Especially internationally, that's who you'll be checking in with, and who will be controlling whether your flight is late. Many smaller domestic codeshare airlines lump their ticket counters in with their partners' -- Delta will probably handle a Delta Connection flight.

But if your flight is Delta operated by Aeroflot, you're going to the Aeroflot counter, and picking up your luggage at the Aeroflot baggage claim. Don't bother looking for Delta. You're an Aeroflot customer.

Things get murky when things go wrong. If Aeroflot is operating your flight and they lose your luggage, you have to deal with them. But if you're flying a "Delta" ticket on Aeroflot and miss your connection, try Aeroflot first, but then go to Delta -- because the ticketing carrier is actually responsible for getting you to your destination.

Why Code Shares Are Bad

Code shares are misleading advertising. When you buy a flight on, say, United Airlines, you expect to have United pilots, United planes, United safety standards, and -- for better or for worse -- United service. But you could end up on one of more than 20 other airlines instead.

That means you may have quite a hike if you're connecting flights. At JFK Airport, Delta flights to Paris are operated by Air France. Delta is in Terminal 3; Air France is in Terminal 1. If you're connecting between a domestic Delta flight and a flight to Paris, you have to switch terminals.

Codeshares may put you on an airline more likely to lose your luggage. According to the U.S. Department of Transportation, in terms of losing luggage in 2009, the bottom five U.S. carriers all operate mostly through codeshares -- Pinnacle, Skywest, Comair, American Eagle, and Atlantic Southeast.

And code shares aren't just annoying. In some cases, they can be actually dangerous. Many routes to smaller cities in the U.S. aren't flown by mainline airlines, but by smaller "regional" carriers who take on confusing names to bamboozle you into thinking they're the same as the big guys. They're not.

A scandal erupted after one of those flights, a Continental Connection flight actually run by Colgan Airlines, crashed in 2009. As chronicled on a cutting episode of Frontline, in the New York Times, and in front of a Congressional panel, regional airlines pay less than the mainline carriers and are allowed to have different sets of safety standards (though all airlines, of course, are monitored by the FAA). Colgan protested the Frontline episode (link opens PDF document), but admitted it had no factual errors.

Regional airlines are a key part of the nation's air infrastructure -- their cheapskate form of flying lets a lot of small cities that would otherwise never have airline service get planes into their towns. But you should at least know what you're getting.

Outside the U.S., codeshares can create some customer service problems. United Airlines code-shares with two dozen international airlines, and the English-language skills of the staff of Adria Airlines may be less than perfect. That's not their fault -- their English is a heck of a lot better than my Slovenian, which is Adria's staff's native language.

And if you have unreasonable prejudices against certain airlines, that should be your business. I refuse to fly Egyptair, for instance. I don't want to buy a ticket on United and find myself on one of their planes.

Why Code Shares Are Good

In situations where you have to fly two different airlines to get to your destination, actively seek out a code share to connect the two carriers. That's because if your whole flight is under one airline's code, it is responsible for getting you all the way to your destination if you miss your connection. If you just book two separate tickets on two separate airlines and miss a connection because the first plane is late, the second airline just treats you as a no-show. That's a big headache.

You can also make money by playing the code share game. Airlines will sell seats on the same planes, under different codes, for entirely different prices. Delta runs a daily flight from New York-JFK to Milan that's sold under both Delta's and Alitalia's codes, so Alitalia can pretend to have a flight to New York. On sample dates I tried, there was a $400 difference between seats under the different codes -- on the same flight!

Who's Flying Whom: Domestic

Here's a guide to U.S. code shares and pseudonyms. Complicating things in the U.S., even the codeshares lie. Regional airlines fly under pseudonyms and then sell tickets under a third name. Here's who claims to be whom:

You think you're on: Alaska Airlines

But you might really be on: American Airlines, Delta Airlines, Era Alaska, Horizon Air, Kenmore Air, Mokulele Airlines, PenAir

You think you're on: AirTran

But you might really be on: SkyWest Airlines

You think you're on: American Airlines

But you might really be on: Horizon Air, American Eagle

You think you're on: American Connection

But you might really be on: Chautauqua Airlines

You think you're on: Continental Airlines

But you might really be on: Amtrak (!), Cape Air, Island Air, United Airlines, US Airways

You think you're on: Continental Connection

But you might really be on: Cape Air, Colgan Air, CommutAir, Gulfstream International Airlines,

You think you're on: Continental Express

But you might really be on: ExpressJet, Chautauqua Airlines

You think you're on: Delta Airlines

But you might really be on: Alaska Airlines, American Eagle, Horizon Air

You think you're on: Delta Connection

But you might really be on: Comair, Atlantic Southeast Airlines, Chautaqua Airlines, Compass, SkyWest, Freedom Airlines, Mesaba Airlines, Pinnacle Airlines, Shuttle America

You think you're on: Frontier Airlines

But you might really be on: Great Lakes Airlines, Lynx Aviation, Republic Airlines

You think you're on: JetBlue

But you might really be on: Cape Air

You think you're on: Midwest Airlines

But you might really be on: Republic Airlines

You think you're on: US Airways

But you might really be on: Continental Airlines, United Airlines, Hawaiian Airlines

You think you're on: US Airways Express

But you might really be on: Air Wisconsin, Chautauqua Airlines, Colgan Air, Republic Airlines, Mesa Airlines, PSA Airlines, Piedmont Airlines, Trans States Airlines

You think you're on: United Airlines

But you might really be on: Continental Airlines, Hawaiian Airlines, Island Air, US Airways

You think you're on: United Express

But you might really be on: Colgan Air, Atlantic Southeast Airlines, ExpressJet Airlines, SkyWest, GoJet Airlines, Mesa Airlines, Shuttle America, Trans States Airlines

Who's Flying Whom: International

The three global airline alliances make their carriers' networks look world-spanning when they're anything but. Usually, an airline's actual network will connect to a partner's hub, and then you're actually flying on the other airline from there. Here's a list of who's in each alliance and their home country. Individual airlines actually have more international codeshare partners than I'm listing here, but these are their core groups. In any case, you should be hyper-aware of who is actually "operating" your international flight, because you'll have to check in with the operating airline when you fly.

OneWorld: American Airlines (U.S.), British Airways (UK), Cathay Pacific (Hong Kong), Finnair (Finland), Iberia (Spain), Japan Airlines (JAL), LAN (Several Latin American countries), Malév (Hungary), Mexicana (Mexico), Qantas (Australia), Royal Jordanian (Jordan)

SkyTeam: Aeroflot (Russia), Aeromexico (Mexico), Air Europa (Spain), Air France, Alitalia (Italy), China Southern Airlines, CSA Czech Airlines, Delta Air Lines (U.S.), KLM Royal Dutch Airlines, Korean Air, Kenya Airways

Star Alliance: Adria Airways (Slovenia), Air Canada, Air China, Air New Zealand, ANA (Japan), Asiana (Korea), Austrian Air, Blue1 (Finland), bmi (UK), Brussels Airlines (Belgium), Continental Airlines (U.S.), Croatia Airlines, Egyptair, Lot Polish Airlines, Lufthansa (Germany), Scandinavian Airlines (Denmark), Shanghai Airlines, Singapore Airlines, South African Airways, Spanair (Spain), Swiss, TAP Portugal, Thai, Turkish Airlines, United Airlines (U.S.) and US Airways (U.S.)

Sascha Segan has been writing for Frommer's since 2001, authoring the books Fly Safe, Fly Smart and for Dummies and collecting Lowell Thomas awards from the Society of American Travel Writers Foundation for his columns in 2007 and 2009. He's also the managing editor for mobile at He lives in Queens, NY with his wife and daughter, who frequently accompany him on his trips.

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