| IATA | ICAO | Airport name | Location |
|---|
| IAB | KIAB | McConnell AFB | Wichita, Kansas, United States |
| IAD | KIAD | Washington Dulles International Airport | Fairfax County and Loudoun County, Virginia (near Washington, DC), United States |
| IAG | KIAG | Niagara Falls International Airport | Niagara Falls, New York, United States |
| IAH | KIAH | George Bush Intercontinental Airport | Houston, Texas, United States |
| IAN | PAIK | Bob Baker Memorial Airport | Kiana, Alaska, United States |
| IAR | UUDL | Yaroslavl Airport | Yaroslavl, Russia |
| IAS | LRIA | Iaşi International Airport | Iaşi, Romania |
| IBE | SKIB | Perales Airport | Ibagué, Colombia |
| IBL | | Indigo Bay Lodge Airport | Bazaruto Island, Mozambique |
| IBM | KIBM | Kimball Municipal Airport (Robert E. Arraj Field) | Kimball, Nebraska, United States |
| IBN | PABN | Devils Mountain Lodge Airport | Nabesna, Alaska, United States |
| IBO | KIBO | Idabel Airport | Idabel, Oklahoma, United States |
| IBZ | LEIB | Ibiza Airport | Ibiza, Spain |
| ICK | SMNI | Nieuw-Nickerie Airport (Maj. Fernandes Airport) | Nieuw-Nickerie, Suriname |
| ICL | KICL | Schenck Field | Clarinda, Iowa, United States |
| ICN | RKSI | Incheon International Airport | Incheon, South Korea, near Seoul |
| ICT | KICT | Wichita Mid-Continent Airport | Wichita, Kansas, United States |
| IDA | KIDA | Idaho Falls Regional Airport | Idaho Falls, Idaho, United States |
| IDG | KIDG | Ida Grove Municipal Airport | Ida Grove, Iowa, United States |
| IDI | KIDI | Indiana County Airport (Jimmy Stewart Field) | Indiana, Pennsylvania, United States |
| IDL | KIDL | Indianola Municipal Airport | Indianola, Mississippi, United States |
| IDP | KIDP | Independence Municipal Airport | Independence, Kansas, United States |
| IDR | VAID | Devi Ahilyabai Holkar International Airport | Indore, Madhya Pradesh, India |
| IEG | EPZG | Zielona Góra Airport | Zielona Góra, Poland |
| IEM | PAWR | Whittier Airport | Whittier, Alaska, United States |
| IEN | KIEN | Pine Ridge Airport | Pine Ridge, South Dakota, United States |
| IER | KIER | Natchitoches Regional Airport | Natchitoches, Louisiana, United States |
| IEV | UKKK | Kiev International Airport | Kyiv, Ukraine |
| IFA | KIFA | Iowa Falls Municipal Airport | Iowa Falls, Iowa, United States |
| IFO | UKLI | Ivano-Frankivsk Airport | Ivano-Frankivsk, Ukraine |
| IFP | KIFP | Laughlin/Bullhead International Airport | Bullhead City, Arizona, United States |
| IGG | PAIG | Igiugig Airport | Igiugig, Alaska, United States |
| IGM | KIGM | Kingman Airport | Kingman, Arizona, United States |
| IGQ | KIGQ | Lansing Municipal Airport | Chicago, Illinois, United States |
| IGR | SARI | Cataratas del Iguazú International Airport | Puerto Iguazú, Misiones, Argentina |
| IGS | ETSI | Ingolstadt Manching Airport | Ingolstadt, Germany |
| IGT | PAGT | Nightmute Airport | Nightmute, Alaska, United States |
| IGU | SBFI | Foz do Iguaçu International Airport | Foz do Iguaçu, Paraná, Brazil |
| IGX | KIGX | Horace Williams Airport | Chapel Hill, North Carolina, United States |
| IHN | OYQN | Qishn Airport | Qishn, Yemen |
| IIB | KIIB | Independence Municipal Airport | Independence, Iowa, United States |
| IIK | PAKI | Kipnuk Airport | Kipnuk, Alaska, United States |
| IIY | KIIY | Washington-Wilkes County Airport | Washington, Georgia, United States |
| IJD | KIJD | Windham Airport | Willimantic, Connecticut, United States |
| IJX | KIJX | Jacksonville Municipal Airport | Jacksonville, Illinois, United States |
| IKA | OIIE | Imam Khomeini International Airport | Tehran, Iran |
| IKE | BGIA | Ikerasak Heliport | Ikerasak, Greenland |
| IKG | KIKG | Kleberg County Airport | Kingsville, Texas, United States |
| IKK | KIKK | Greater Kankakee Airport | Kankakee, Illinois, United States |
| IKO | PAKO | Nikolski Air Station | Nikolski, Alaska, United States |
| IKT | UUII | Irkutsk International Airport | Irkutsk, Russia |
| IKV | KIKV | Ankeny Regional Airport | Ankeny, Iowa, United States |
| ILE | KILE | Skylark Field | Killeen, Texas, United States |
| ILG | KILG | New Castle Airport | Wilmington, Delaware, United States |
| ILI | PAIL | Iliamna Airport | Iliamna, Alaska, United States |
ILL | KILL | Willmar Municipal Airport (John L. Rice Field) (closed) | Willmar, Minnesota, United States |
| ILL | BGLL | Illorsuit Heliport | Illorsuit, Greenland |
| ILM | KILM | Wilmington International Airport | Wilmington, North Carolina, United States |
| ILN | KILN | Airborne Airpark | Wilmington, Ohio, United States |
| ILO | RPVI | Iloilo International Airport | Iloilo City, Philippines |
| ILZ | LZZI | Žilina Airport | Žilina, Slovakia |
| IMB | SYIB | Imbaimadai Airport | Imbaimadai, Guyana |
| IMF | VEIM | Tulihal Airport | Imphal, India |
| IML | KIML | Imperial Municipal Airport | Imperial, Nebraska, United States |
| IMM | KIMM | Immokalee Airport | Immokalee, Florida, United States |
| IMT | KIMT | Ford Airport | Iron Mountain / Kingsford, Michigan, United States |
| INC | | Yinchuan Airport | Yinchuan, China |
| IND | KIND | Indianapolis International Airport | Indianapolis, Indiana, United States |
ING | SAWA | Lago Argentino Airport (closed 2006) | El Calafate, Santa Cruz, Argentina |
| INH | FQIN | Inhambane Airport | Inhambane, Mozambique |
| INI | LYNI | Niš Constantine the Great Airport | Niš, Serbia |
| INJ | KINJ | Hillsboro Municipal Airport | Hillsboro, Texas, United States |
| INK | KINK | Winkler County Airport | Wink, Texas, United States |
| INL | KINL | Falls International Airport | International Falls, Minnesota, United States |
| INN | LOWI | Innsbruck Kranebitten Airport | Innsbruck, Austria |
| INR | PAIN | McKinley National Park Airport | McKinley Park, Alaska, United States |
| INS | KINS | Creech Air Force Base | Indian Springs, Nevada, United States |
| INT | KINT | Smith Reynolds Airport | Winston-Salem, North Carolina, United States |
| INU | ANYN | Nauru International Airport | Yaren, Nauru |
| INV | EGPE | Inverness Airport | Inverness, Scotland, United Kingdom |
| INW | KINW | Winslow-Lindbergh Regional Airport | Winslow, Arizona, United States |
| IOA | LGIO | Ioannina National Airport | Ioannina, Greece |
| IOB | KIOB | Mount Sterling-Montgomery County Airport | Mount Sterling, Kentucky, United States |
| IOM | EGNS | Isle of Man Airport | Ronaldsway, Isle of Man, United Kingdom |
| IOR | EIIM | Inishmore Aerodrome | Inishmore, Ireland |
| IOS | SBIL | Ilhéus Jorge Amado Airport | Ilhéus, Bahia, Brazil |
| IOW | KIOW | Iowa City Municipal Airport | Iowa City, Iowa, United States |
| IPC | SCIP | Mataveri International Airport | Easter Island, Chile |
| IPE | RPMV | Ipil Airport | Zamboanga del sur, Philippines |
| IPH | WMKI | Sultan Azlan Shah Airport | Ipoh, Perak, Malaysia |
| IPI | SKIP | San Luis Airport | Ipiales, Colombia |
| IPJ | KIPJ | Lincolnton-Lincoln County Regional Airport | Lincolnton, North Carolina, United States |
| IPL | KIPL | Imperial County Airport | Imperial, California, United States |
| IPT | KIPT | Williamsport Regional Airport | Williamsport, Pennsylvania, United States |
IPW | EGSE | Ipswich Airport ipw (closed 1996) | Ipswich, England |
| IQQ | SCDA | Diego Aracena International Airport | Iquique, Chile |
| IQT | SPQT | Crnl. FAP Francisco Secada Vignetta International Airport | Iquitos, Loreto, Peru |
| IRJ | SANL | Capitán Vicente Almandos Almonacid Airport | La Rioja, Argentina |
| IRK | KIRK | Kirksville Regional Airport | Kirksville, Missouri, United States |
| IRO | FEFI | Birao Airport | Birao, Central African Republic |
| IRS | KIRS | Kirsch Municipal Airport | Sturgis, Michigan, United States |
| ISB | OPRN | Islamabad International Airport | Rawalpindi, Pakistan |
| ISE | LTFC | Suleyman Demirel Airport | Isparta, Turkey |
| ISK | VANR | Gandhinagar Airport | Nasik, India |
| ISM | KISM | Kissimmee Gateway Airport | Orlando, Florida, United States |
| ISN | KISN | Sloulin Field International Airport | Williston, North Dakota, United States |
| ISO | KISO | Kinston Regional Jetport (at Stallings Field) | Kinston, North Carolina, United States |
| ISP | KISP | Long Island MacArthur Airport | Islip, New York, United States |
| ISQ | KISQ | Schoolcraft County Airport | Manistique, Michigan, United States |
| IST | LTBA | Atatürk International Airport | Istanbul, Turkey |
| ISU | ORSU | Sulaimaniyah International Airport | Sulaimaniyah, Kurdistan,Iraq |
| ISW | KISW | Alexander Field South Wood County Airport | Wisconsin Rapids, Wisconsin, United States |
| ISZ | KISZ | Blue Ash Airport | Cincinnati, Ohio, United States |
| ITH | KITH | Ithaca Tompkins Regional Airport | Ithaca, New York, United States |
| ITM | RJOO | Osaka International Airport | Itami (near Osaka), Japan |
| ITO | PHTO | Hilo International Airport | Hilo, Hawaii, United States |
| ITR | KITR | Kit Carson County Airport | Burlington, Colorado, United States |
| IUE | NIUE | Hanan International Airport | Alofi, Niue |
| IVC | NZNV | Invercargill Airport | Invercargill, New Zealand |
| IVL | EFIV | Ivalo Airport | Ivalo, Finland |
| IVR | YIVL | Inverell Airport | Inverell, New South Wales, Australia |
| IWA | KIWA | Phoenix-Mesa Gateway Airport | Phoenix, Arizona, United States |
| IWD | KIWD | Gogebic-Iron County Airport | Ironwood, Michigan, United States |
| IWH | KIWH | Wabash Municipal Airport | Wabash, Indiana, United States |
| IWI | KIWI | Wiscasset Airport | Wiscasset, Maine, United States |
| IWO | RJAW | Iwo Jima Air Base | Iwo Jima, Bonin Islands, Japan |
| IWS | KIWS | West Houston Airport | Houston, Texas, United States |
| IXA | VEAT | Agartala Airport (Singerbhil Airport) | Agartala, India |
| IXB | VEBD | Bagdogra Airport | Bagdogra, India |
| IXC | VICG | Chandigarh Airport | Chandigarh, India |
| IXD | VIAL | Allahabad Airport / Bamrauli Air Force Base | Allahabad, India |
| IXE | VOML | Mangalore International Airport | Mangalore, India |
| IXG | VABM | Belgaum Airport | Belgaum, India |
| IXH | VEKR | Kailashahar Airport | Kailashahar, India |
| IXI | VELR | Lilabari Airport (North Lakhimpur Airport) | Assam, India |
| IXJ | VIJU | Jammu Airport (Satwari Airport) | Jammu, India |
| IXK | VAKS | Junagadh Airport (Keshod Airport) | Keshod, India |
| IXL | VILH | Leh Kushok Bakula Rimpochee Airport | Leh, India |
| IXM | VOMD | Madurai Airport | Madurai, India |
| IXN | VEKW | Khowai Airport | Khowai, India |
| IXP | VIPK | Pathankot Airport | Pathankot, India |
| IXQ | VEKM | Kamalpur Airport | Kamalpur, India |
| IXR | VERC | Birsa Munda Airport (Ranchi Airport) | Ranchi, India |
| IXS | VEKU | Silchar Airport (Kumbhirgram Airport) | Silchar, India |
| IXT | VEPG | Pasighat Airport (Passighat Airport) | Pasighat (Passighat), India |
| IXU | VAAU | Aurangabad Airport (Chikkalthana Airport) | Aurangabad, Maharashtra, India |
| IXV | VEAN | Along Airport | Along, Arunachal Pradesh, India |
| IXW | VEJS | Sonari Airport | Jamshedpur, India |
| IXY | VAKE | Kandla Airport (Gandhidham Airport) | Gandhidham / Kandla, India |
| IXZ | VOPB | Vir Savarkar Airport (Port Blair Airport) | Port Blair, India |
| IYK | KIYK | Inyokern Airport | Inyokern, California, United States |
| IYS | PAWS | Wasilla Airport | Wasilla, Alaska, United States |
| IZA | KIZA | Santa Ynez Airport | Santa Ynez, California, United States |
| IZG | KIZG | Eastern Slopes Regional Airport | Fryeburg, Maine, United States |