| IAA | Igarka Airport | Igarka |  Russian Federation |
| IAB | McConnell Air Force Base | Wichita |  United States of America |
| IAD | Washington Dulles International | Washington | United States of America |
| IAG | Niagara Falls International Airport | Niagara Falls | United States of America |
| IAH | George Bush Intercontinental | Houston | United States of America |
| IAM | In Amenas Airport | In Amenas |  Algeria |
| IAN | Bob Barker Memorial Airport | Kiana | United States of America |
| IAO | Sayak Airport | |  Philippines |
| IAQ | Bahregan Airport | Bushehr |  Iran (Islamic Republic of) |
| IAR | Yaroslavl Airport | Yaroslavl | Russian Federation |
| IAS | Iasi Airport | Iasi |  Romania |
| IAU | Iaura Airport | Port Moresby |  Papua New Guinea |
| IBA | Ibadan Airport | Ibadan |  Nigeria |
| IBE | Ibague Airport | Ibague |  Colombia |
| IBI | Iboki Airport | Hoskins | Papua New Guinea |
| IBL | Indigo Bay Lodge | Vilanculos |  Mozambique |
| IBO | Ibo Airport | Pemba | Mozambique |
| IBP | Iberia Airport | Puerto Maldonado |  Peru |
| IBZ | Ibiza Airport | Ibiza |  Spain |
| ICA | Icabaru Airport | Puerto Ordaz |  Venezuela (Bolivarian Republic of) |
| ICI | Cicia Airport | Vava'u |  Fiji |
| ICK | Nieuw Nickerie Airport | Paramaribo |  Suriname |
| ICL | Schenck Field | Omaha | United States of America |
| ICN | Seoul (Incheon) Airport | Seoul |  Korea (Republic of) |
| ICO | Sicogon Island Airport | Roxas City | Philippines |
| ICR | Nicaro Airport | Guantanamo |  Cuba |
| ICT | Wichita Dwight D. Eisenhower National Airport | Wichita | United States of America |
| ICY | Icy Bay Airport | Yakutat | United States of America |
| IDA | Fanning Field Airport | Idaho Falls | United States of America |
| IDB | Idre Airport | Sveg |  Sweden |
| IDC | Ila Da Chilonzuene | Vilanculos | Mozambique |
| IDF | Idiofa Airport | Kinshasa |  Congo (Democratic Republic of the) |
| IDG | Ida Grove Municipal Airport | Sioux City | United States of America |
| IDI | ndiana County Airport (Jimmy Stewart Field) | Johnstown | United States of America |
| IDK | Indulkana Airport | Coober Pedy |  Australia |
| IDN | Indagen Airport | Lae | Papua New Guinea |
| IDO | Rio Airport | Palmas |  Brazil |
| IDP | Independence Municipal Airport | Tulsa | United States of America |
| IDR | Devi Ahilyabai Holkar Airport | Indore |  India |
| IEG | Babimost Airport | Zielona Gora |  Poland |
| IEJ | Iejima Airport | Okinawa |  Japan |
| IES | Riesa Airport | Dresden |  Germany |
| IEV | Zhulyany Airport | Kiev |  Ukraine |
| IFA | Iowa Falls Airport | Mason City | United States of America |
| IFF | Iffley Airport | Normanton | Australia |
| IFH | Hesa Airport | Isfahan | Iran (Islamic Republic of) |
| IFJ | Isafjordur Airport | Isafjordur |  Iceland |
| IFL | Innisfail Airport | Cairns | Australia |
| IFN | Isfahan International Airport | Isfahan | Iran (Islamic Republic of) |
| IFO | Ivano-Frankovsk Airport | Ivano-Frankovsk | Ukraine |
| IFP | Laughlin Bullhead International Airport | Bullhead City | United States of America |
| IGA | Inagua Airport | Inagua |  Bahamas |
| IGB | Ingeniero Jacobacci Airport | San Carlos de Bariloche |  Argentina |
| IGE | Iguela Airport | Libreville |  Gabon |
| IGG | Igiugig Airport | Igiugig | United States of America |
| IGH | Ingham Airport | Palm Island | Australia |
| IGM | Kingman Airport | Bullhead City | United States of America |
| IGN | Maria Cristina Airport | Ozamis City | Philippines |
| IGO | Chigorodo Airport | Apartado | Colombia |
| IGR | Cataratas Airport | Iguazu | Argentina |
| IGS | Ingolstadt-manching | Munich | Germany |
| IGT | Magas Airport | Ordzhonikidzevskaya | Russian Federation |
| IGU | Foz do Iguaçu International Airport | Iguassu Falls | Brazil |
| IHA | Niihama Airport | Kochi | Japan |
| IHC | Inhaca Airport | Maputo | Mozambique |
| IHN | Qishn Airport | Sana'a |  Yemen |
| IHO | Ihosy Airport | Fort Dauphin |  Madagascar |
| IHR | Iran Shahr | Chah-Bahar | Iran (Islamic Republic of) |
| IHU | Ihu Airport | Goroka | Papua New Guinea |
| IIA | Inishmaan Airport | Shannon |  Ireland |
| IIL | Ilaam Airport | Ilaam | Iran (Islamic Republic of) |
| IIN | Nishinoomote Airport | Yakushima | Japan |
| IIS | Nissan Island Airport | Rabaul | Papua New Guinea |
| IJK | Izhevsk Airport | Izhevsk | Russian Federation |
| IJU | J. Batista Bos Filho Airport | Santa Maria | Brazil |
| IJX | Jacksonville Municipal Airport | Springfield | United States of America |
| IKA | Imam Khomeini Airport | Tehran | Iran (Islamic Republic of) |
| IKB | Wilkes County Airport | Winston-Salem | United States of America |
| IKI | Iki Airport | Iki | Japan |
| IKK | Greater Kankakee Airport | Chicago | United States of America |
| IKL | Ikela Airport | Kisangani | Congo (Democratic Republic of the) |
| IKO | Nikolski AFS | Nikolski | United States of America |
| IKP | Inkerman Airport | Karumba | Australia |
| IKS | Tiksi Airport | Tiksi | Russian Federation |
| IKT | Irkutsk Airport | Irkutsk | Russian Federation |
| ILA | Illaga Airport | Tembagapura |  Indonesia |
| ILB | Ilha Solteira Airport | Aracatuba | Brazil |
| ILE | Skylark Field | Killeen | United States of America |
| ILF | Ilford | Gods Lake Narrows |  Canada |
| ILG | Greater Wilmington Airport | Wilmington | United States of America |
| ILH | Illis Airbase Airport | Nuremberg | Germany |
| ILI | Iliamna Airport | Iliamna | United States of America |
| ILK | Ilaka Airport | Antananarivo | Madagascar |
| ILL | Willmar Municipal Airport (John L. Rice Field) | Brainerd | United States of America |
| ILM | Wilmington International Airport | Wilmington | United States of America |
| ILN | Wilmington Air Park | Dayton | United States of America |
| ILO | Iloilo International Airport | Iloilo | Philippines |
| ILP | Ile Des Pins Airport | Ile Des Pins |  New Caledonia |
| ILQ | Ilo Airport | Tacna | Peru |
| ILR | Ilorin Airport | Ilorin | Nigeria |
| ILU | Kilaguni Airport | Mombasa |  Kenya |
| ILX | Ileg Airport | Madang | Papua New Guinea |
| ILY | Glenegedale Airport | Islay |  United Kingdom of Great Britain and Northern Ireland |
| ILZ | Zilina Airport | Poprad/Tatry |  Slovakia |
| IMA | Iamalele Airport | Alotau | Papua New Guinea |
| IMB | Imbaimadai Airport | Georgetown |  Guyana |
| IMD | Imonda Airport | Vanimo | Papua New Guinea |
| IMF | Imphal International Airport (Tulihal Airport) | Imphal | India |
| IMG | Inhaminga Airport | Beira | Mozambique |
| IMI | Ine Island Airport | Majuro |  Marshall Islands |
| IMK | Simikot Airport | Nepalganj |  Nepal |
| IML | Imperial Airport | McCook | United States of America |
| IMM | Immokalee Airport | Naples | United States of America |
| IMN | Imane Airport | Lae | Papua New Guinea |
| IMO | Zemio Airport | Bangui |  Central African Republic |
| IMP | Imperatriz Airport | Imperatriz | Brazil |
| IMT | Ford Airport | Iron Mountain | United States of America |
| IMZ | Nimroz Airport | Herat |  Afghanistan |
| INA | Inta Airport | Inta | Russian Federation |
| INB | Independence Airport/Savannah Airport/Mango Creek | Belize City |  Belize |
| INC | Yinchuan Airport | Yinchuan |  China |
| IND | Indianapolis International Airport | Indianapolis | United States of America |
| INE | Chinde Airport | Quelimane | Mozambique |
| INF | In Guezzam | Tamanrasset | Algeria |
| ING | Lago Argentino Airport | El Calafate | Argentina |
| INH | Inhambane Airport | Inhambane | Mozambique |
| INI | Constantine The Great International Airport | Nis |  Serbia |
| INJ | Injune Airport | Roma | Australia |
| INK | Wink Airport | Hobbs | United States of America |
| INL | Falls International Airport | International Falls | United States of America |
| INM | Innamincka Airport | Olympic Dam | Australia |
| INN | Innsbruck-kranebitten Airport | Innsbruck |  Austria |
| INO | Inongo Airport | Kinshasa | Congo (Democratic Republic of the) |
| INQ | Inisheer Airport | Shannon | Ireland |
| INS | Creech Air Force Base | Las Vegas | United States of America |
| INT | Smith-Reynolds Airport | Winston-Salem | United States of America |
| INU | Nauru International Airport | Tarawa |  Nauru |
| INV | Inverness Airport | Inverness | United Kingdom of Great Britain and Northern Ireland |
| INW | Winslow-Lindbergh Airport | Show Low | United States of America |
| INX | Inanwatan Airport | Fak Fak | Indonesia |
| INY | Inyati Airport | Londolozi |  South Africa |
| INZ | In Salah Airport | In Salah | Algeria |
| IOA | Ioannina Airport | Ioannina |  Greece |
| IOK | Iokea Airport | Port Moresby | Papua New Guinea |
| IOM | Ronaldsway Airport | Isle Of Man | United Kingdom of Great Britain and Northern Ireland |
| ION | Impfondo Airport | Brazzaville |  Congo |
| IOP | Ioma Airport | Popondetta | Papua New Guinea |
| IOR | Kilronan Airport | Shannon | Ireland |
| IOS | Ilheus Jorge Amado Airport | Ilheus | Brazil |
| IOU | Ile Ouen Airport | Noumea | New Caledonia |
| IOW | Iowa City Airport | Cedar Rapids | United States of America |
| IPA | Ipota Airport | Tanna |  Vanuatu |
| IPC | Mataveri International Airport | Easter Island |  Chile |
| IPE | Ipil Airport | Pagadian | Philippines |
| IPG | Ipiranga Airport | Tabatinga | Brazil |
| IPH | Sultan Azlan Shah Airport | Ipoh |  Malaysia |
| IPI | San Luis Airport | Ipiales | Colombia |
| IPL | Imperial County Airport | Imperial | United States of America |
| IPN | Usiminas Airport | Ipatinga | Brazil |
| IPT | Lycoming County Airport | Williamsport | United States of America |
| IPU | Ipiau Airport | Ilheus | Brazil |
| IPW | Ipswich | Boston | United Kingdom of Great Britain and Northern Ireland |
| IQM | Qiemo Airport | Qiemo | China |
| IQN | Qingyang Airport | Qingyang | China |
| IQQ | Cavancha Airport | Iquique | Chile |
| IQT | C.F. Secada Airport | Iquitos | Peru |
| IRA | Kirakira Airport | Kirakira |  Solomon Islands |
| IRB | Iraan Municipal Airport | Midland | United States of America |
| IRC | Circle City Airport | Fort Yukon | United States of America |
| IRD | Ishurdi Airport | Rajshahi |  Bangladesh |
| IRE | Irece Airport | Lencois | Brazil |
| IRG | Lockhart River Airport | Weipa | Australia |
| IRI | Nduli Airport | Iringa |  Tanzania |
| IRJ | Capitan Vicente Almando Airport | La Rioja | Argentina |
| IRK | Kirksville Regional Airport | Kirksville | United States of America |
| IRM | Igrim Airport | Igrim | Russian Federation |
| IRN | Iriona Airport | Roatan |  Honduras |
| IRO | Birao Airport | Bangui | Central African Republic |
| IRP | Matari Airport | Kisangani | Congo (Democratic Republic of the) |
| IRS | Kirsch Municipal Airport | Kalamazoo | United States of America |
| ISA | Mount Isa Airport | Mount Isa | Australia |
| ISB | Islamabad International Airport | Islamabad |  Pakistan |
| ISC | St Marys Airport | Montgomery | United States of America |
| ISD | Iscuande Airport | Guapi | Colombia |
| ISE | Isparta Airport | Isparta |  Turkey |
| ISG | Ishigaki Airport | Ishigaki | Japan |
| ISH | Ischia Airport | Ischia |  Italy |
| ISI | Isisford Airport | Longreach | Australia |
| ISJ | Isla Mujeres Airport | Cancun |  Mexico |
| ISK | Gandhinagar Airport | Mumbai | India |
| ISL | Ataturk Airport | Istanbul | Turkey |
| ISM | Kissimmee Gateway Airport | Orlando | United States of America |
| ISN | Sloulin Field International Airport | Williston | United States of America |
| ISO | Stallings Field Airport | Greenville | United States of America |
| ISP | Long Island Mac Arthur Airport | Ronkonkoma | United States of America |
| ISQ | Schoolcraft County Airport | Escanaba | United States of America |
| ISS | Wiscasset Airport | Augusta | United States of America |
| IST | Istanbul New Airport | Istanbul | Turkey |
| ISU | Sulaimaniyah International Airport | Sulaimaniyah |  Iraq |
| ISW | Alexander Field Airport | Wausau | United States of America |
| ITA | Itacoatiara Airport | Manaus | Brazil |
| ITB | Itaituba Airport | Santarem | Brazil |
| ITE | Itubera Airport | Ilheus | Brazil |
| ITH | Tompkins County Airport | Ithaca | United States of America |
| ITI | Itambacuri Airport | Governador Valadares | Brazil |
| ITK | Itokama Airport | Popondetta | Papua New Guinea |
| ITM | Itami Airport | Osaka | Japan |
| ITN | Itabuna Airport | Ilheus | Brazil |
| ITO | Hilo International Airport | Hilo | United States of America |
| ITP | Itaperuna Airport | Campos | Brazil |
| ITQ | Itaqui Airport | Uruguaiana | Brazil |
| ITR | Francisco Vilela do Amaral Airport / Itumbiara Air | Uberlandia | Brazil |
| IUE | Hanan Airport | Niue Island |  Niue |
| IUL | Ilu Airport | Wamena | Indonesia |
| IUM | Summit Lake Airport | Prince George | Canada |
| IUS | Inus Airport | Rabaul | Papua New Guinea |
| IVA | Ambanja Airport | Nossi-be | Madagascar |
| IVC | Invercargill Airport | Invercargill |  New Zealand |
| IVG | Ivangrad Airport | Podgorica |  Montenegro |
| IVH | Ivishak Airport | Prudhoe Bay/Deadhorse | United States of America |
| IVL | Ivalo Airport | Ivalo |  Finland |
| IVO | Chivolo/Chibolo | Barranquilla | Colombia |
| IVR | Inverell Airport | Armidale | Australia |
| IVW | Inverway Airport | Kununurra | Australia |
| IWA | Ivanova Airport | Ivanovo | Russian Federation |
| IWD | Gogebic County Airport | Ironwood | United States of America |
| IWJ | Iwami Airport | Masuda | Japan |
| IWO | Iwo Jima Airbase Airport | Hachijo Jima | Japan |
| IWS | West Houston | Houston | United States of America |
| IXA | Singerbhil Airport | Agartala | India |
| IXB | Bagdogra Airport | Bagdogra | India |
| IXC | Chandigarh Airport | Chandigarh | India |
| IXD | Bamrauli Airport | Allahabad | India |
| IXE | Mangaluru International Airport | Mangalore | India |
| IXG | Sambre Airport | Belgaum | India |
| IXH | Kailashahar Airport | Aizawl | India |
| IXI | North Lakhimpur Airport | Lilabari | India |
| IXJ | Satwari Airport | Jammu | India |
| IXK | Keshod Airport | Diu | India |
| IXL | Bakula Rimpoche Airport | Leh | India |
| IXM | Madurai Airport | Madurai | India |
| IXN | Khowai Airport | Agartala | India |
| IXP | Pathankot Airport | Dharamsala | India |
| IXQ | Kamalpur Airport | Agartala | India |
| IXR | Birsa Munda International Airport | Ranchi | India |
| IXS | Kumbhirgram Airport | Silchar | India |
| IXT | Pasighat Airport | Dibrugarh | India |
| IXU | Chikkalthana Airport | Aurangabad | India |
| IXV | Along Airport | Dibrugarh | India |
| IXW | Sonari Airport | Ranchi | India |
| IXY | Kandla Airport | Bhuj | India |
| IXZ | Port Blair Airport | Port Blair | India |
| IYK | Inyokern Airport | Bakersfield | United States of America |
| IZO | Izumo Airport | Izumo | Japan |
| IZT | Ixtepec Airport | Huatulco | Mexico |