How Are Airport Abbreviations Determined

The three-letter code is determined by first ensuring that it’s unique and not in use by any other entity. The code might be assigned based on the name of the airport, the name of the city, or some other meaningful and relevant identifier if those letters are already taken.

How are airline codes assigned?

There’s actually no special formula or process behind the assigning of airline codes. Instead, they are simply chosen by the airline and must be unique. As a result, new airlines may not get their first choice as it may be already taken by an existing carrier. Most older airlines have gone with two letters.

Are airport codes unique?

Since the code contains only three letters, the possible combinations are limited and consequently the IATA codes are not unique in some cases, with the same code used to designate two different airports. Therefore, the ICAO codes were created because aviation requires a unique designation for airports.