Airport codes & guides

World Airports

Airport codes are acronyms that in the 1930s arose out of convenience, which brought the practice to pilots for destination identification. Initially, the United States pilots used the two-letter airport codes assigned from the National Weather Service (NWS) for identifying cities, regions, states, and other locations.

What are the airport codes?

By the late 1940s, this two-letter system became unmanageable for some towns and cities that appear without an NWS identifier. Hence, the use of two-letter airport codes allowed only a few hundred combinations. Due to that fact, a new, three-letter system of airport codes was quickly implemented. The three-letter acronym airport codes' method allowed for around 17,576 permutations, assuming all letters must be used in conjunction with each other.

How airports get their codes

The three-letter code is generally determined and approved by first ensuring that it is unique and not currently used by any other entity. The airport code may be assigned mainly based on the name of the particular airport, the city's name, or even some other relevant and meaningful identifier key names if those letters are already taken. As a result of airport coding, no two airports worldwide share the same airport code.

It is noteworthy to mention that two official entities approve different airport codes to each airport worldwide. These are the International Civil Aviation Organization, shortened as ICAO, and the other is the International Air Transport Association depicted as IATA. Below you will find further information about each airport code.

ICAO airport codes

The International Civil Aviation Organization (ICAO) is an arm of the United Nations, ensuring the aviation regulations jive within different continents and countries. ICAO assigns airport codes typically used by air traffic control and those airlines that crafting their flight plans. Those ICAO airport codes are determined with four letters length. The 1st letter of the ICAO airport code describes the country, and the remaining three letters signify the specific airport. ICAO changes the techniques and principles of international air navigation and always tries to develop and plan international air transport to ensure safety and airports' orderly growth. The ICAO headquarters are mainly located in the Quartier International of Montreal, Quebec, in Canada.

The ICAO adopts standards and practices concerning air navigation, infrastructure, prevention of unlawful interference, flight inspection, and facilitation of border-crossing issues for international aviation. It defines air accident protocols followed by transport safety authorities in regions signatory to the Chicago Convention on International Civil Aviation.

Airport codes are named right after the first three letters of the city in which the airport is located — for instance, ATL stands for Atlanta, SIN serves Singapore, ASU stands for Asunción, DEN for Denver; MEX for Mexico City, IST for Istanbul, etc. There is also a combination of the airport code letters in each name. For example, ALA stands for Almaty (initially known as Alma-Ata), GDL for Guadalajara, EWR for Newark, JNB for Johannesburg, SLC for Salt Lake City, HKG for Hong Kong, and WAW for Warsaw. Some airports based in the United States retained NWS airport codes and appended an X at the end, like LAX for Los Angeles, PHX for Phoenix, and PDX for Portland.

Some airport codes do not fit the regular scheme like that. For example, across several regions, or municipalities use airport codes derived right from some of their letters, resulting in MSP for Minneapolis–Saint Paul, DTW for Detroit–Wayne County, DFW for Dallas/Fort Worth, and RDU for Raleigh–Durham. Other airports, especially those serving cities with various airports, use airport codes derived from the airport's name, like CDG for Paris' Charles de Gaulle. In some cases, the airport code comes directly from the airport's unofficial name. For example, Kahului Airport uses the code OGG, which stands for local aviation pioneer Jimmy Hogg.

IATA airport codes

The International Air Transport Association (IATA) is an airline trade association that assigns the particular airport codes to which most people are more familiar with ICAO airport codes. IATA stands for the following meanings, such as the location identifier, IATA as a station code. IATA a three-letter geocode that designated various airports along with their metropolitan areas throughout the entire world. IATA characters are prominently produced on baggage tags attached at airport check-in desks; boarding passes, etc.

The assignment of these three-letter geocode is owned by IATA Resolution 763, and it is governed by the IATA's headquarters based in Montreal. The airport codes are published semiannually within the IATA Airline Coding Directory. Furthermore, IATA also displays codes for railway stations as well as for airport handling entities. A list of airports that are sorted by the IATA airport code is always available.

IATA airport codes are determined with the three-letters shown on booking, flight timetables, or airline tickets. For instance, Fort Lauderdale-Hollywood International Airport uses the IATA code "FLL," while the Amsterdam Schiphol Airport uses "AMS.” The IATA code for Berlin Schönefeld Airport is SXF, and its ICAO code is EDDB The airport code is the same as the last three letters that the ICAO determines, but not regularly.