The ICAO airport code is a four-letter alphanumeric code designating each airport around the world. These codes are defined by the International Civil Aviation Organization. The ICAO codes are used by air traffic control and airline operations such as flight planning. They are not the same as the IATA codes encountered by the general public, which are used for airline timetables, reservations, and baggage handling. ICAO codes are also used to identify weather stations, whether or not they are located at airports.
Unlike the IATA codes, the ICAO codes have a regional structure, i.e. the first letter is allocated by continent, the second is a country within the continent, the remaining two are used to identify each airport.
AG = Solomon Islands AN = Nauru AY = Papua New Guinea BG = Greenland BI = Iceland C = Canada DA = Algeria DB = Benin DF = Burkina Faso DG = Ghana DI = Côte d'Ivoire DN = Nigeria DR = Niger DT = Tunisia DX = Togolese Republic EB = Belgium ED = Germany EE = Estonia EF = Finland EG = United Kingdom of Great Britain and Northern Ireland EH = Netherlands EI = Ireland EK = Denmark EL = Luxembourg EN = Norway EP = Poland ES = Sweden ET = Germany EV = Latvia EY = Lithuania FA = South Africa FB = Botswana FC = Republic of the Congo FD = Swaziland FE = Central African Republic FG = Equatorial Guinea FH = Azores, Ascension Island FI = Mauritius FJ = British Indian Ocean Territory FK = Cameroon FL = Zambia FM = Comoros, Madagascar, Mayotte, Réunion FN = Angola FO = Gabon FP = São Tomé and Príncipe FQ = Mozambique FS = Seychelles FT = Chad FV = Zimbabwe FW = Malawi FX = Lesotho FY = Namibia FZ = Democratic Republic of the Congo GA = Mali GB = The Gambia GC = Canary Islands (Spain) GF = Sierra Leone GG = Guinea-Bissau GL = Liberia GM = Morocco GO = Senegal GQ = Mauritania GS = Western Sahara GU = Guinea GV = Cape Verde HA = Ethiopia HB = Burundi HC = Somalia HE = Egypt HF = Djibouti HH = Eritrea HK = Kenya HL = Libya HR = Rwanda HS = Sudan HT = Tanzania HU = Uganda K = United States of America (Continental) LA = Albania LB = Bulgaria LC = Cyprus LD = Croatia LE = Spain LF = France LG = Greece LH = Hungary LI = Italy LJ = Slovenia LK = Czech Republic LL = Israel LM = Malta LN = Monaco LO = Austria LP = Portugal LQ = Bosnia and Herzegovina LR = Romania LS = Switzerland LT = Turkey LU = Moldova LW = Macedonia LX = Gibraltar LY = Serbia and Montenegro LZ = Slovakia MB = Turks and Caicos MD = Dominican Republic MG = Guatemala MH = Honduras MK = Jamaica MM = Mexico MN = Nicaragua MP = Panama MR = Costa Rica MS = El Salvador MT = Haiti MU = Cuba MW = Cayman Islands MY = Bahamas MZ = Belize NC = Cook Islands NF = Fiji, Tonga NG = Tuvalu NI = Niue NL = Wallis and Futuna NS = Samoa NT = French Polynesia NV = Vanuatu NW = New Caledonia NZ = New Zealand OA = Afghanistan OB = Bahrain OD = Yemen OE = Saudi Arabia OI = Iran OJ = Jordan OK = Kuwait OL = Lebanon OM = United Arab Emirates OO = Oman OP = Pakistan OR = Iraq OS = Syria OT = Qatar PA = United States of America (Alaska) PB = Baker Island PC = Phoenix Island PG = Northern Marianas, Guam PH = United States of America (Hawaii) PJ = Johnston Atoll PK = Marshall Islands PL = Kiribati PM = Midway Island PT = Federated States of Micronesia, Palau PW = Wake Island RC = Taiwan RJ = Japan (also RO) RK = South Korea RP = Philippines SA = Argentina SB = Brazil SC = Chile SE = Ecuador SF = Falkland Islands SG = Paraguay SK = Colombia SL = Bolivia SM = Suriname SO = French Guiana SP = Peru SU = Uruguay SV = Venezuela SY = Guyana TA = Antigua and Barbuda TB = Barbados TD = Dominica TF = Guadeloupe TG = Grenada TI = U.S. Virgin Islands TJ = Puerto Rico TK = Saint Kitts and Nevis TL = Saint Lucia TN = Netherlands Antilles, Aruba TQ = Anguilla TR = Montserrat TT = Trinidad and Tobago TU = British Virgin Islands TV = Saint Vincent and the Grenadines TX = Bermuda U = Russia (except UA, UB, UG, UK, UM and UT) UA = Kazakhstan, Kyrgyzstan UB = Azerbaijan UG = Armenia, Georgia UK = Ukraine UM = Belarus UT = Tajikistan, Turkmenistan, Uzbekistan VA = India (also VE, VI and VO) VC = Sri Lanka VD = Cambodia VG = Bangladesh VH = Hong Kong VL = Laos VM = Macao VN = Nepal VQ = Bhutan VR = Maldives VT = Thailand VV = Vietnam VY = Myanmar WA = Indonesia (also WI, WQ, WR) WB = Malaysia (also WM), Brunei Darussalam WP = Timor-Leste WS = Singapore Y = Australia Z = People's Republic of China (except ZK and ZM) ZK = North Korea ZM = Mongolia
EBBR: Belgium - Brussels International Airport, Brussels (IATA code BRU)
FAJS: South Africa - Johannesburg International Airport, Johannesburg (IATA code JNB)
KBOS: United States - Logan International Airport, Boston (IATA code BOS)
LIRF: Italy - Leonardo Da Vinci International Airport, Fiumicino, near Rome (IATA code FCO)
OMDB: United Arab Emirates - Dubai International Airport, Dubai (IATA code DBX)
YSCB: Australia - Canberra (IATA code CBR)
Others are less logical; very few UK airports are obvious, for example:
EGLL - London Heathrow, EGKK - London Gatwick ()
In the United States and Canada, most airports which have been assigned three-letter codes by their respective regulatory agencies use the same code with leading "K" or "C" as their ICAO code; e.g., YYC (Calgary International Airport, Calgary, Alberta) and CYYC, IAD (Dulles International Airport, Chantilly, Virginia) and KIAD. These codes are not to be confused with radio callsigns, even though both countries use four-letter callsigns starting with those letters.
A list of airports, sorted by IATA code, is available.