Secrets of Three Letter Airport Codes Revealed

That’s a Daily Mail piece that Alan H. forwards to me.

There are three letter airport codes that match the first three letters of their city name, like SYD for Sydney and MEL for Melbourne, Australia.

They don’t get to use the first three letters for Detroit Metropolitan Airport, since DET is actually the old Detroit City Airport (now named ‘Coleman A. Young Municipal Airport’ and without scheduled commercial service).

New York’s JFK airport is JFK, LaGuardia takes three letters from its name, and Hong Kong (HKG) does as well.

Denver gets DEN but many mistakenly or colloquially refer to it as ‘DIA’.

What the article taught me that I didn’t actually know:

  • Early airports used two letter codes based on weather stations, and those legacy airports get an ‘X’ (hence LAX, SUX).
  • Canadian airports start with a Y because of a naming convention derived from radio stations (West Coast stations – and airports – have ICAO indicators starting with a K, as with radio all of Canadian has a unique starting letter)..

I’ve always been amused by airport codes, possibly because I lived in Fresno (FAT) for a time. The airport long wanted to call itself Fresno Yosemite International (“FYI”) to trick people into thinking you’d need to fly there to get to Yosemite, it’s a good place to do it but not the only place. But it’s still just FAT (“Fresno Air Terminal”).

I always wanted to ticket an itinerary from Fresno, California to Fukuoka, Japan. Or from Fresno to Pensacola, Florida.

About Gary Leff

Gary Leff is one of the foremost experts in the field of miles, points, and frequent business travel - a topic he has covered since 2002. Co-founder of frequent flyer community, emcee of the Freddie Awards, and named one of the "World's Top Travel Experts" by Conde' Nast Traveler (2010-Present) Gary has been a guest on most major news media, profiled in several top print publications, and published broadly on the topic of consumer loyalty. More About Gary »

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  1. Living in Cincinnati, I know why our airport is CVG – named after Covington, Kentucky, but I don’t know why there doesn’t seem to be a CIN at all… Our smaller airport is LUK (Lunken Airport)

  2. JL flies from FUK nonstop to Yakushima Island, Japan – KUM!

    It appears that Carroll, IA already had “CIN” for its airport.

    I remember in the early 90s when WN still had service to DET, I think a few others sporadically did over the years.

  3. I have an upcoming flight from Singapore to Helsinki (SIN-HEL) on Finnair. I’m not looking forward to the layover in Helsinki…I hear it can be eternal.

  4. Too bad this article is pretty much dead wrong on all the important facts. Urban legends being perpetuated.

    Reality is quite boring in today’s world. Codes are allocated by the Manager – Coding & MITA at IATA in Montreal based upon available options. You can always request a specific code allocation and he does a good job trying to match up the most appropriate available choice.

  5. lolz at your desired tickets. They’re better than mine from when I was younger and gigglier. I wanted to go from Charlotte to Cancun to Knoxville.

  6. If I recall correctly, Gary, DEN is now the airport code for Denver International Airport; but DIA was the airport code for the old Stapleton International Airport, which was the main international airport which served the Denver metropolitan area.

    Old habits are difficult to break, I suppose…

  7. More interesting to me is the naming of intersections in airways (which are 5 characters) . They make it a point to try to name then relating to what is underneath (BOSOX in Boston, RINGY in Sarasota, etc). When I was flying out of Caldwell, NJ, the FAA was having a horrible time getting some equipment for instrument landings working and certified. It took years longer than planned. Eventually they named the intersection over there FUBAR. There USED to be an intersection above Patterson, NJ called PATRN (pronounced “pattern”) which had to be renamed because of confusion with the defined term “pattern” often used for landing checkpoints.

  8. The IATA code for Stapleton International Airport was DEN; they were able to transfer the code to Denver International Airport because Stapleton was decomissioned just hours before the new airport officially opened. The new airport is typically referred to locally as DIA as an abbreviation of its name.

  9. I always appreciated the irony around the Kansas City airport (about 150 mile out of town I might add!). It is MCI, which must have frustrated those persons working at/with Sprint.

  10. you’re so juvenile. And I’m sure that you are proud of yourself. 😀

    Btw, I had lunch at Elephant Jumps last week. Great as ever. And the owner was super friendly as usual. I may have to go back there again this week as I am working from Tysons. Want to join me?

  11. The Denver airport opened in 1995, after several missed opening dates. A friend of mine said DIA stood for “Done In Awhile”.

  12. Har har. But what about flying from Fresno to Apalapsili?!?! Or Charata???

    I a sorry you had to live in Fresno. Now were you in Chowcilla or Corocan? I assume you were there for a prison sentence. Why else would someone go to Fresno (or anywhere else in the San Joaquin Valley)

  13. Many airports are coded from their old names. That’s why Louisville is SDF (Standiford Field), and Orlando is MCO (McCoy Field). Each code must be unique in the world. Once an airport is coded, it never loses its code. So, if a city builds a new airport, it gets a new code. When Disney came to Orlando, the airport was completely rebuilt, but since the old section (now a freight area) was incorporated, it kept the MCO designation. Every airport has a code, even our little general aviation airports. Ottawa County, OH has PCW for its small airport, once the home of Island Airways, which flew Ford Tri-Motors to South Bass Island, OH, and claimed it was the smallest airline in the world. It’s gone now. When Daimler and Chrysler were one company, the corporate jets flew out of PTK (Pontiac, MI) 3 days a week for STT (Stuttgart, Germany).

  14. @Retired Lawyer

    “So, if a city builds a new airport, it gets a new code.”

    Not 100%, see the case of HKG, where the airpot code moved from Kai Tak to the new airport.

  15. Someone mentioned in a previous post that IATA assigns the 3-letter airport codes used for ticketing, etc. ICAO (International Civil Aviation Organization) assigns 4-letter codes that sometime, but not always, incorporate the IATA codes. ICAO has divided the planet into zones and the first letter of the 4-letter code reflects the zone in which the airport is located. The U.S. is in zone “K”, so all U.S. airports have a code like ‘KABC’ (used for example only). Much of northern Europe including Great Britain and Ireland are in ICAO zone “E”, so the four letter code for London Heathrow is EGLL, for Gatwick it’s EGKK, for Dublin it’s EIDW, for Frankfurt it’s EDDF, and for Munich it’s EDDM. However, France, southern Europe, and much of the former “eastern bloc” countries are in zone L. Therefore, Paris Chas. de Gaulle is LFPG, Orly is LFPO, Milan Linate is LIML, Prague is LKPR, and Salzburg is LOWS. Most of South America is in zone “S”, so Buenos Aires Ezeiza airport is SAEZ. Australia is in zone Y, so the ICAO code for Sydney-Kingsford Smith is YSSY. I could go on and on, but surely you’re bored by now.

  16. The old Denver Stapleton and new Denver Int’l airports were open and operational at the same time during a transition period. While both airports were open they obviously could not have the same id. DEN was Stapleton and DIA was used for the new airport. When Stapleton officially closed, the Denver airport operator requested and was granted the reinstatement of DEN as the identifier for Denver Int’l Airport. DIA is an unofficial reference. DEN is the official id.

  17. “esenn”: while it is true the new DEN airport was “open” for a short period while the old DEN airport was still in use, it was never coded as DIA–its temporary code while things were tested, etc., was DVX. The DEN code was moved from Stapleton to the new Freddie Pena Int’l (sarcasm) during the overnight period when Stapleton closed and conga lines of equipment were moved down I-70 to the new airport. Some local government or media type started referring to the new DEN as DIA and it stuck, unofficially. Kind of like how the Tucson Airport Authority keeps calling its airport TIA, when it is (and has been) TUS, and of course the local media has gone along for the ride.

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