Demystifying Airport Codes: How Are They Chosen, Exactly?

Airports generally have three letter codes, and they tend to confuse people, given the lack of consistent naming mechanisms. If you’ve ever been curious about where an airport code comes from, I’d like to take a closer look at this, as there’s a handy website that will tell you. I think avgeeks in particular will really enjoy this.

Airportcod.es tells you how airport codes are chosen

There are over 11,000 airports in the world with three letter IATA airport code assignments. Since there are over 40,000 aviation facilities around the globe, these are typically reserved for airports with commercial traffic, or else we’d run out of codes.

How are those codes actually decided, though? Globally, there’s no consistent rhyme or reason to that, and that’s why airportcod.es is an awesome website. In addition to virtually all major airports just being listed in grid format, you can also search your preferred airport. Then when you click the link, you’ll see an explanation for the name.

The most common ways airport codes are chosen

As you’d expect, there’s no consistent, single system by which airport codes are chosen. After all, there are only a limited number of codes, so not all airports can get their first choice.

If I were to roughly rank things, I’d say the most straightforward and common naming mechanism is simply based on the name of the destination. We’re talking airport codes like Addis Ababa (ADD) and Auckland (AKL). As you can see, that’s not always going to be consecutive letters, but they could be taken from various parts of the city’s name.

There’s a slight variance on that, where the preferred code wasn’t available, so they sub in another letter. For example, I’m sure Dubai (DXB) would’ve loved to use the code Dublin (DUB) has, but instead, they subbed in an “X” for the “U.”

I’d say the next most common naming mechanism is based on the person or thing the airport is named after, which could be different than the place it’s located. We’re talking airports like New York John F. Kennedy (JFK) and Paris Charles de Gaulle (CDG).

Then there’s the category of airport codes that cause confusion, because the letters seemingly have nothing to do with the current names of the airports. For example, Orlando (MCO) has a code based on its old name of McCoy Airforce Base, while Chicago O’Hare (ORD) has a code based on its former name of Orchard Field.

Lastly, there’s the category of airport codes that are downright confusing to most, like Montreal Trudeau (YUL). While Canadian airport codes consistently start with “Y,” the “UL” is named after a nearby radio beacon. That’s not exactly what you’d expect an airport to be named after, but…!

Bottom line

There’s a lot of inconsistency between airport codes. With so many airports out there and only a limited number of codes, not all airports get their first choice. While the most common system is for airport codes to be based on a name of the destination they serve, many are also based on the name of the airport, especially when it’s named after a person.

Then there are all kinds of airports that have codes either based on historical names, or based on random things, and those are ones that many travelers have a hard time making sense of. If you’re curious about the origins of airport codes, check out airportcod.es.

Did you find any airport codes which surprised you?