ICAO airport code prefixes
Unlike IATA codes, four-letter ICAO codes are geographic: the first letter tells you the world region. Read KJFK as K (the contiguous United States) plus JFK. Here is the broad first-letter scheme with examples.
How ICAO codes are structured
An ICAO location indicator has four letters. The first letter, and often the second, encodes the region and country; the remaining letters identify the specific airport. So EGLL is E (northern Europe), G (the United Kingdom) and LL for London Heathrow. The matching IATA code, LHR, carries no such geography. See IATA vs ICAO for the full comparison.
ICAO first-letter regions
| First letter | Region | Examples |
|---|---|---|
| K | Contiguous United States | KJFK, KLAX |
| P | Alaska, Hawaii and the eastern Pacific | PANC, PHNL |
| C | Canada | CYYZ, CYVR |
| T | The Caribbean | TJSJ, TNCM |
| M | Mexico and Central America | MMMX, MROC |
| S | South America | SBGR, SAEZ |
| B | Greenland, Iceland and Kosovo | BIKF, BGGH |
| E | Northern Europe | EGLL, EHAM |
| L | Southern Europe and the Mediterranean | LFPG, LEMD |
| U | Russia and most post-Soviet states | UUEE, UUDD |
| O | The Middle East and Pakistan | OMDB, OPKC |
| V | South and Southeast Asia | VIDP, VTBS |
| W | Maritime Southeast Asia | WSSS, WIII |
| R | East Asia (Japan, Korea, Taiwan) | RJTT, RKSI |
| Z | China, Mongolia and North Korea | ZBAA, ZSPD |
| Y | Australia | YSSY, YMML |
| N | The South Pacific | NZAA, NFFN |
| F | Southern and central Africa | FAOR, FACT |
| G | Western Africa and the north-west | GCTS, GMMN |
| H | North-eastern Africa | HECA, HKJK |
| D | Parts of West Africa | DNMM, DGAA |
This is the broad scheme; a few regions split further on the second letter, and a handful of territories are grouped for historical reasons.
Frequently asked questions
What does K mean in an ICAO code?
K is the ICAO prefix for the contiguous United States. So JFK becomes KJFK, LAX becomes KLAX, and O'Hare becomes KORD.
Why does JFK become KJFK?
JFK is the three-letter IATA code. The four-letter ICAO code adds the regional prefix K (contiguous US) to the front, giving KJFK. The two codes describe the same airport for different users.
Are IATA codes geographic like ICAO codes?
No. IATA three-letter codes are not systematically geographic, so you cannot tell the country from an IATA code. ICAO four-letter codes are, because the first letter (or two) encodes the region.
Keep reading: IATA vs ICAO · How airport codes work · all guides.