IATA vs ICAO airport codes: what is the difference?

What an IATA code is

IATA location identifiers contain three characters and support commercial aviation, reservations, ticketing, baggage, cargo and travel distribution. IATA's official database includes not only airports but also metropolitan areas, rail stations, bus stations, ferry ports and other intermodal locations, so a three-letter code is not always one airport.

What an ICAO code is

ICAO Doc 7910 lists four-letter location indicators for geographical locations and related aeronautical fixed-service stations. States formulate and manage indicators under ICAO procedures. They are widely used in flight planning, weather, aeronautical information and operational systems.

Common airport examples

One airport commonly has both codes, but the formats cannot always be converted mechanically.

• London Heathrow: IATA LHR, ICAO EGLL.
• New York JFK: IATA JFK, ICAO KJFK.
• Beijing Capital: IATA PEK, ICAO ZBAA.
• Tokyo Haneda: IATA HND, ICAO RJTT.

Why many US codes look similar

Many airports in the contiguous United States use an ICAO indicator formed by adding K before the familiar IATA code, such as JFK/KJFK and LAX/KLAX. That is not a global rule and should not be applied mechanically to Alaska, Hawaii, Canada, Europe or Asia. Use authoritative data instead of guessing.

A city code may not be an airport

Multi-airport cities can have metropolitan codes. WAS represents the Washington area, while IAD, DCA and BWI identify individual airports; NYC is a New York area code, while JFK, LGA and EWR identify airports. A city code is convenient for travel searches, but coordinate distance requires a specific airport.

Why some airports have only an ICAO code

IATA codes are driven by commercial-airline and intermodal requirements, so not every small, military, general-aviation or non-scheduled airport receives one. ICAO location indicators cover a different set of operational locations, leaving many records with an ICAO code but no IATA code.

Can codes change or be reused?

Airport renaming, relocation, closure and commercial changes can alter code status. IATA aims to keep current identifiers clear for industry data exchange, but historical codes, metropolitan codes and separate coding systems can still cause confusion. Date-sensitive or operational work should use current authoritative sources.

Which code should you enter here?

FlightRouteMap searches both IATA and ICAO codes. Route URLs prefer an airport's IATA code because it is short, shareable and familiar to travellers. The airport detail panel displays both systems so you can verify that the selected record is the intended airport.