ICAO
ICAO Airport Code
A four-letter code assigned by the International Civil Aviation Organization for air traffic control and flight planning.
ICAO airport codes are four-letter identifiers assigned by the International Civil Aviation Organization for use in air traffic control, flight planning, and aviation communications. Unlike IATA codes, ICAO codes follow a regional structure: the first letter indicates the region (K for contiguous US, C for Canada, E for Northern Europe, etc.), and remaining letters identify the specific airport. Examples include KJFK (New York JFK), EGLL (London Heathrow), and RJTT (Tokyo Haneda).
Common Causes
Impact & Duration
Impact Level
N/A - Identification standard, not an operational delay
Typical Duration
N/A
Frequently Asked Questions
Why do US airports have ICAO codes starting with K?
The letter K was assigned to the contiguous United States in the ICAO regional coding system. Alaska uses P (Pacific), Hawaii uses PH, and US territories have various prefixes.
When would I see ICAO codes vs IATA codes?
Passengers typically see IATA codes on tickets and baggage tags. Pilots and air traffic controllers use ICAO codes in flight plans, weather reports, and ATC communications.
Related Terms
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