Type NYC into a flight search and you'll get results from three different airports: JFK, LaGuardia, and usually Newark. But NYC isn't an airport at all. It's a city code, IATA's way of saying "this metropolitan area, whichever runway." Understanding city code vs airport code saves real money when you book, because the code you type decides whether you see one airport's fares or the whole metro area's.
The distinction trips people up because the two code systems look identical. Three capital letters, same search boxes, same luggage tags. An airport code identifies one physical airport: JFK is John F. Kennedy International, and only that building. A city code identifies a metro area with multiple airports, so the booking system can bundle them. Chicago is CHI, which covers O'Hare and Midway. Washington is WAS, covering Dulles, Reagan National, and Baltimore-Washington. London is LON: Heathrow, Gatwick, Stansted, City, Luton, and Southend, six airports under one umbrella.
City code vs airport code: what each one means
Some city codes are easy to read. TYO is Tokyo (Haneda and Narita), PAR is Paris (Charles de Gaulle and Orly). Others reuse a single airport's own code, which is where the confusion sharpens. HOU is both the city code for Houston and the airport code for Hobby, while Intercontinental (IAH) sits under the same city umbrella. The code you type determines whether you get one airport's fares or the whole metro area's.
Why maintain both? Because travelers search by city and airlines price by market. If you want "New York to London," nobody wants to run six separate searches for JFK-LHR, LGA-LGW, and all the combinations. Typing LON to NYC runs the whole matrix at once. Behind the scenes, these codes exist largely for fare pricing: the fare is built for the city pair, and then each airline routes you through whichever airport it likes.
City codes do change, and that is the part that caught Newark travelers off guard. For years, EWR sat inside the NYC city code. Then, in 2022, Newark was pulled out of the NYC multi-airport city code for fare-pricing purposes. Searching NYC stopped bundling Newark's fares by default, even though no runway moved and the airport kept its EWR code. The airport code is the fixed label on the building; the city code is an administrative grouping, and administrations revise groupings.
The reverse surprise is HOU and BKK. Bangkok's city code BKK is also Suvarnabhumi's airport code, with Don Mueang (DMK) tucked underneath. Type BKK expecting the metro area and you may only get one airport's inventory, depending on the booking engine. The letters don't tell you which system you're in. The context does. And in a raw data file, there is no context at all: NYC and JFK are both three capital letters in the same column. That is why a code database needs a flag separating city codes from airport codes, so an import script doesn't quietly treat a metro area as a runway.
So how do you use them well? If you live near one of several airports, search the city code first to see the full fare picture, then compare against each airport individually. Newark is the classic case: with it out of the NYC pricing bundle, EWR fares can diverge from JFK and LGA, and the city-code search won't always catch that. When you actually book, check which airport you're flying into, because the cheapest fare in a metro search has a way of landing you at the airport farthest from home.
Three letters can mean a building or a whole region. NYC, CHI, WAS, LON, TYO, and PAR are regions wearing the same costume as the buildings.
Frequently asked questions
What is an IATA city code?
A three-letter code representing a metropolitan area with more than one airport, such as NYC for New York or WAS for Washington. It lets booking systems search and price fares across all the airports in the metro area at once.
Is NYC the code for JFK?
No. NYC is the city code for the New York metro area. JFK is the airport code for John F. Kennedy International. NYC historically covered JFK, LaGuardia, and Newark, though Newark was removed from the NYC fare-pricing city code in 2022.
Which airports are under the WAS city code?
Washington's WAS city code covers Dulles (IAD), Reagan National (DCA), and Baltimore-Washington (BWI). Searching WAS finds fares into all three.
Why was Newark removed from the NYC city code?
The change, effective in 2022, was about airline fare pricing rather than operations. EWR kept its airport code and its flights; it was the administrative grouping for NYC pricing that changed.
Can a city code be identical to an airport code?
Yes. Houston's HOU is both the city code for the metro area and the airport code for Hobby airport. The meaning depends on which system the search is using.
Search the full US airport code database
Sources: IATA airport code reference; Cranky Flier on the 2022 Newark/NYC change. Figures verified October 2026.