Aviation Glossary - ICAO Code

ICAO Code

The station identifier, in ICAO format, is included in all reports to identify the station to which the coded report applies.

The ICAO airport code is a four-letter alphanumeric code designating each airport around the world. The ICAO codes are used for flight planning by air traffic controllers and airline operation departments. These codes are not the same as the International Air Transport Association (IATA) codes encountered by the general public used for reservations, baggage handling and in airline timetables. ICAO codes are also used to identify weather stations located on- or off-airport.

Unlike the IATA codes, the ICAO codes have a regional structure. For example, the first letter is allocated by continent, the second is a country within the continent; the remaining two are used to identify each airport.

In the contiguous U. S., ICAO station identifiers are coded K followed by the three-letter IATA identifier. For example, the Seattle, Washington (IATA identifier SEA) becomes the ICAO identifier KSEA.

ICAO station identifiers in Alaska, Hawaii, and Guam begin with the continent code P, followed by the proper country code (A, H, and G respectively), and the two-letter airport identifier.

Examples:

PANC Anchorage, AK
PAOM Nome, AK
PHNL Honolulu, HI
PHKO Keahole Point, HI
PGUM Agana, Guam
PGUA Anderson AFB, Guam

Canadian station identifiers begin with C, followed by the country code, and the two-letter airport identifier.

Examples:

CYYZ Toronto, Canada
CYYC Calgary Canada
CYQB Quebec, Canada
CYXU London, Canada
CZUM Churchill Falls, Canada

Mexican and western Caribbean station identifiers begin with M, followed by the proper country code and two-letter airport identifier.

Examples:

MMMX Mexico City, Mexico
MUGM Guantanamo Bay, Cuba
MDSD Santo Domingo, Dominican Republic
MYNN Nassau, Bahamas

Eastern Caribbean station identifiers begin with T, followed by the proper country code, and airport identifier.

Examples:

TJSJ San Juan, Puerto Rico
TIST Saint Thomas, Virgin Islands

For a list of Alaskan, Hawaiian, Canadian, Mexican, Pacific, and Caribbean ICAO identifiers see FAA Order 7350.7. For a complete worldwide listing, see ICAO Document 7910, “Location Indicators.” Both are available on-line.

source: FAA/NOAA Aviation Weather Services (AC 00-45G)