192 airports
| IATA | Airport Name | City | Country |
|---|---|---|---|
| OEA | O'Neal Airport | Lawrenceville | 🇺🇸 United States |
| ONL | O'Neill Municipal Airport–John L Baker Field | O'Neill | 🇺🇸 United States |
| JNB | O.R. Tambo International Airport | Johannesburg | 🇿🇦 South Africa |
| OKC | OKC Will Rogers World Airport | Oklahoma City | 🇺🇸 United States |
| ODC | Oakdale Airport | Oakdale | 🇺🇸 United States |
| OKY | Oakey Army Aviation Centre | 🇦🇺 Australia | |
| PTK | Oakland County International Airport | Pontiac | 🇺🇸 United States |
| OAM | Oamaru Airport | 🇳🇿 New Zealand | |
| OBN | Oban Airport | North Connel | 🇬🇧 UK |
| PDA | Obando Cesar Gaviria Trujillo Airport | Puerto Inírida | 🇨🇴 Colombia |
| OBD | Obano Airport | Obano | 🇮🇩 Indonesia |
| OBF | Oberpfaffenhofen Airport | Weßling | 🇩🇪 Germany |
| OBX | Obo Airport | Obo | 🇵🇬 Papua New Guinea |
| OBC | Obock Airport | Obock | 🇩🇯 Djibouti |
| OCF | Ocala International Airport - Jim Taylor Field | Ocala | 🇺🇸 United States |
| OCE | Ocean City Municipal Airport | Ocean City | 🇺🇸 United States |
| MJX | Ocean County Airport | Toms River | 🇺🇸 United States |
| OCA | Ocean Reef Club Airport | Key Largo | 🇺🇸 United States |
| NTU | Oceana Naval Air Station | Virginia Beach | 🇺🇸 United States |
| OCN | Oceanside Municipal Airport | Oceanside | 🇺🇸 United States |
| CEU | Oconee County Regional Airport | Clemson | 🇺🇸 United States |
| ONJ | Odate Noshiro Airport | Kitaakita | 🇯🇵 Jepun |
| ODE | Odense Hans Christian Andersen Airport | Odense | 🇩🇰 Denmark |
| ODS | Odesa International Airport | Odesa | 🇺🇦 Ukraine |
| ODT | Odessa Schlemeyer Field | Odessa | 🇺🇸 United States |
| KEO | Odienne Airport | Odienne | 🇨🇮 Cote d’Ivoire |
| OEC | Oecusse Route of the Sandalwood International Airport | Oecussi-Ambeno | 🇹🇱 Timor-Leste |
| OPI | Oenpelli Airport | 🇦🇺 Australia | |
| LAH | Oesman Sadik Airport | Labuha-Halmahera Island | 🇮🇩 Indonesia |
| OFF | Offutt Air Force Base | Omaha | 🇺🇸 United States |
| OFU | Ofu Airport | Ofu | 🇦🇸 American Samoa |
| OGA | Ogallala Municipal Airport Searle Field | Ogallala | 🇺🇸 United States |
| OGD | Ogden Hinckley Airport | Ogden | 🇺🇸 United States |
| OGS | Ogdensburg International Airport | Ogdensburg | 🇺🇸 United States |
| OGE | Ogeranang Airport | 🇵🇬 Papua New Guinea | |
| OGM | Ogobsucum Airport | Ustupu | 🇵🇦 Panama |
| YOG | Ogoki Post Airport | Ogoki Post | 🇨🇦 Kanada |
| ATO | Ohio University Airport | Albany | 🇺🇸 United States |
| ESO | Ohkay Owingeh Airport | Espanola | 🇺🇸 United States |
| OHD | Ohrid St. Paul the Apostle Airport | Ohrid | 🇲🇰 North Macedonia |
| OYK | Oiapoque Airport | Oiapoque | 🇧🇷 Brazil |
| OIT | Oita Airport | Oita | 🇯🇵 Jepun |
| OKQ | Okaba Airport | Okaba | 🇮🇩 Indonesia |
| OKV | Okao Airport | Okao | 🇵🇬 Papua New Guinea |
| OKF | Okaukuejo Airport | Okaukuejo | 🇳🇦 Namibia |
| OKJ | Okayama Momotaro Airport | Okayama | 🇯🇵 Jepun |
| OBE | Okeechobee County Airport | Okeechobee | 🇺🇸 United States |
| OHH | Okha Airport | Okha | 🇷🇺 Russia |
| OHO | Okhotsk Airport | Okhotsk | 🇷🇺 Russia |
| OKI | Oki Global Geopark Airport | Okinoshima | 🇯🇵 Jepun |
| OKE | Okinoerabu Airport | Wadomari | 🇯🇵 Jepun |
| OKM | Okmulgee Regional Airport | Okmulgee | 🇺🇸 United States |
| OKN | Okondja Airport | Okondja | 🇬🇦 Gabon |
| OKG | Okoyo Airport | Okoyo | 🇨🇬 Congo - Brazzaville |
| OKP | Oksapmin Airport | Oksapmin | 🇵🇬 Papua New Guinea |
| OKL | Oksibil Airport | Oksibil | 🇮🇩 Indonesia |
| OKT | Oktyabrskiy Airport | Kzyl-Yar | 🇷🇺 Russia |
| OIR | Okushiri Airport | Okushiri Island | 🇯🇵 Jepun |
| OSJ | Ol Seki Naboisho Airstrip | Mara Simba | 🇰🇪 Kenya |
| OLG | Olare Orok Airfield | Mara | 🇰🇪 Kenya |
| OVR | Olavarria Airport | Olavarria | 🇦🇷 Argentina |
| CCI | Olavo Cecco Rigon Airport | Concórdia | 🇧🇷 Brazil |
| OLB | Olbia Costa Smeralda Airport | Olbia (SS) | 🇮🇹 Itali |
| YOC | Old Crow Airport | Old Crow | 🇨🇦 Kanada |
| OLH | Old Harbor Airport | Old Harbor | 🇺🇸 United States |
| ONK | Olenyok Airport | Olenyok | 🇷🇺 Russia |
| OLV | Olive Branch Airport | Olive Branch | 🇺🇸 United States |
| ONY | Olney Municipal Airport | Olney | 🇺🇸 United States |
| OLY | Olney Noble Airport | Olney-Noble | 🇺🇸 United States |
| OLO | Olomouc Airport | Olomouc | 🇨🇿 Czechia |
| OLQ | Olsobip Airport | Olsobip | 🇵🇬 Papua New Guinea |
| SZY | Olsztyn-Mazury Airport | Szymany | 🇵🇱 Poland |
| OLM | Olympia Regional Airport | Olympia | 🇺🇸 United States |
| OLP | Olympic Dam Airport | Olympic Dam | 🇦🇺 Australia |
| OLZ | Olyokminsk Airport | Olyokminsk | 🇷🇺 Russia |
| OMK | Omak Airport | Omak | 🇺🇸 United States |
| MBY | Omar N Bradley Airport | Moberly | 🇺🇸 United States |
| OMB | Omboue Hospital Airport | Omboue | 🇬🇦 Gabon |
| OMG | Omega Airport | Omega | 🇳🇦 Namibia |
| OMI | Omidiyeh Airport | Omidiyeh | 🇮🇷 Iran |
| OSE | Omora Airport | Omora | 🇵🇬 Papua New Guinea |
| OMS | Omsk Central Airport | Omsk | 🇷🇺 Russia |
| OND | Ondangwa Airport | Ondangwa | 🇳🇦 Namibia |
| ONU | Ono-i-Lau Airport | Ono-i-Lau | 🇫🇯 Fiji |
| ONB | Ononge Airport | Onange Mission | 🇵🇬 Papua New Guinea |
| OOT | Onotoa Airport | Onotoa | 🇰🇮 Kiribati |
| ONS | Onslow Airport | 🇦🇺 Australia | |
| ONT | Ontario International Airport | Ontario | 🇺🇸 United States |
| ONO | Ontario Municipal Airport | Oregon | 🇺🇸 United States |
| ODD | Oodnadatta Airport | 🇦🇺 Australia | |
| FVR | Oombulgurri Airport | Oombulgurri | 🇦🇺 Australia |
| OBL | Oostmalle Airfield | Zoersel | 🇧🇪 Belgium |
| YBS | Opapimiskan Lake Airport | Opapimiskan Lake | 🇨🇦 Kanada |
| OPB | Open Bay Airport | Maitanakunai | 🇵🇬 Papua New Guinea |
| YOI | Opinaca Aerodrome | Éléonore Mine | 🇨🇦 Kanada |
| OPW | Opuwa Airport | Opuwa | 🇳🇦 Namibia |
| OMR | Oradea International Airport | Oradea | 🇷🇴 Romania |
| RAX | Oram Airport | 🇵🇬 Papua New Guinea | |
| ORN | Oran Es-Sénia (Ahmed Ben Bella) International Airport | Es-Sénia | 🇩🇿 Algeria |
| TAF | Oran Tafraoui Airport | Tafraoui | 🇩🇿 Algeria |
| RGO | Orang (Chongjin) Airport | Hoemun-ri | 🇰🇵 North Korea |
| OAG | Orange Airport | Orange | 🇦🇺 Australia |
| MGJ | Orange County Airport | Montgomery | 🇺🇸 United States |
| OGB | Orangeburg Municipal Airport | Orangeburg | 🇺🇸 United States |
| OMD | Oranjemund Airport | Oranjemund | 🇳🇦 Namibia |
| ORP | Orapa Airport | Orapa | 🇧🇼 Botswana |
| RBS | Orbost Airport | 🇦🇺 Australia | |
| ESD | Orcas Island Airport | Eastsound | 🇺🇸 United States |
| OKB | Orchid Beach Airport | Orchid Beach | 🇦🇺 Australia |
| ODR | Ord River Airport | Ord River | 🇦🇺 Australia |
| DSN | Ordos Ejin Horo International Airport | Ordos | 🇨🇳 China |
| OGU | Ordu–Giresun Airport | Ordu | 🇹🇷 Turkiye |
| REN | Orenburg Central Airport | Orenburg | 🇷🇺 Russia |
| MOA | Orestes Acosta Airport | Moa | 🇨🇺 Cuba |
| OXO | Orientos Airport | Orientos | 🇦🇺 Australia |
| ORJ | Orinduik Airport | Orinduik | 🇬🇾 Guyana |
| FNU | Oristano-Fenosu Airport | Oristano | 🇮🇹 Itali |
| ORX | Oriximiná Airport | Oriximiná | 🇧🇷 Brazil |
| JDO | Orlando Bezerra de Menezes Airport | Juazeiro do Norte | 🇧🇷 Brazil |
| ORL | Orlando Executive Airport | Orlando | 🇺🇸 United States |
| MCO | Orlando International Airport | Orlando | 🇺🇸 United States |
| SFB | Orlando Sanford International Airport | Orlando | 🇺🇸 United States |
| MBK | Orlando Villas Boas Regional Airport | Matupá | 🇧🇷 Brazil |
| UMU | Orlando de Carvalho Airport | Umuarama | 🇧🇷 Brazil |
| ORE | Orléans–Saint-Denis-de-l'Hôtel Airport | Saint-Denis-de-l'Hôtel, Loiret | 🇫🇷 France |
| ORW | Ormara Airport | Ormara Raik | 🇵🇰 Pakistan |
| OMC | Ormoc Airport | Ormoc City | 🇵🇭 Philippines |
| CBS | Oro Negro Airport | Cabimas | 🇻🇪 Venezuela |
| ORC | Orocue Airport | Orocue | 🇨🇴 Colombia |
| OVE | Oroville Municipal Airport | Oroville | 🇺🇸 United States |
| TXC | Orsha Airport - Balbasovo Air Base | Orsha | 🇧🇾 Belarus |
| OSW | Orsk Airport | Orsk | 🇷🇺 Russia |
| ORA | Orán Airport | Orán | 🇦🇷 Argentina |
| URZ | Orūzgān Airport | Orūzgān | 🇦🇫 Afghanistan |
| ITM | Osaka Itami International Airport | Osaka | 🇯🇵 Jepun |
| OSN | Osan Air Base | Pyeongtaek | 🇰🇷 South Korea |
| OSO | Osborne Mine Airport | 🇦🇺 Australia | |
| OSC | Oscoda Wurtsmith Airport | Oscoda | 🇺🇸 United States |
| OSS | Osh International Airport | Osh | 🇰🇬 Kyrgyzstan |
| OHI | Oshakati Airport | Oshakati | 🇳🇦 Namibia |
| YOO | Oshawa Executive Airport | Oshawa | 🇨🇦 Kanada |
| OIM | Oshima Airport | Izu Oshima | 🇯🇵 Jepun |
| OSI | Osijek Airport | Osijek(Klisa) | 🇭🇷 Croatia |
| OOA | Oskaloosa Municipal Airport | Cedar | 🇺🇸 United States |
| OSK | Oskarshamn Airport | Oskarshamn | 🇸🇪 Sweden |
| UKK | Oskemen International Airport | Ust-Kamenogorsk (Oskemen) | 🇰🇿 Kazakhstan |
| OSL | Oslo-Gardermoen International Airport | Oslo (Gardermoen) | 🇳🇴 Norway |
| ZYL | Osmany International Airport | Sylhet | 🇧🇩 Bangladesh |
| OSG | Ossima Airport | Ossima | 🇵🇬 Papua New Guinea |
| OST | Ostend-Bruges International Airport | Oostende | 🇧🇪 Belgium |
| OXB | Osvaldo Vieira International Airport | Bissau | 🇬🇼 Guinea Bissau |
| AGV | Oswaldo Guevara Mujica Airport | Acarigua | 🇻🇪 Venezuela |
| OTJ | Otjiwarongo Airport | Otjiwarongo | 🇳🇦 Namibia |
| OTO | Otog Banner Wulan Airport | Wulan | 🇨🇳 China |
| OTQ | Otog Front Banner Oljoq Airport | Otog Front Banner | 🇨🇳 China |
| YND | Ottawa / Gatineau Airport | Gatineau | 🇨🇦 Kanada |
| YRO | Ottawa / Rockcliffe Airport | Ottawa | 🇨🇦 Kanada |
| YOW | Ottawa Macdonald-Cartier International Airport | Ottawa | 🇨🇦 Kanada |
| OTM | Ottumwa Regional Airport | Ottumwa | 🇺🇸 United States |
| OTU | Otu Airport | Remedios | 🇨🇴 Colombia |
| ODA | Ouadda Airport | Ouadda | 🇨🇫 Central African Republic |
| OUA | Ouagadougou Thomas Sankara International Airport | Ouagadougou | 🇧🇫 Burkina Faso |
| OUG | Ouahigouya Airport | Ouahigouya | 🇧🇫 Burkina Faso |
| ODJ | Ouanda Djallé Airport | Ouanda Djallé | 🇨🇫 Central African Republic |
| OFI | Ouango Fitini Airport | Ouango Fitini | 🇨🇮 Cote d’Ivoire |
| AJN | Ouani Airport | Ouani | 🇰🇲 Comoros |
| OZZ | Ouarzazate International Airport | Ouarzazate | 🇲🇦 Maghribi |
| ODY | Oudomsay Airport | Oudomsay | 🇱🇦 Laos |
| OUH | Oudtshoorn Airport | Oudtshoorn | 🇿🇦 South Africa |
| OUI | Ouessant Airport | Ushant | 🇫🇷 France |
| OUE | Ouesso Airport | 🇨🇬 Congo - Brazzaville | |
| OUD | Oujda Angads Airport | Ahl Angad | 🇲🇦 Maghribi |
| OUL | Oulu Airport | Oulu / Oulunsalo | 🇫🇮 Finland |
| OUM | Oum Hadjer Airport | Oum Hadjer | 🇹🇩 Chad |
| OIA | Ourilândia do Norte Airport | Ourilândia do Norte | 🇧🇷 Brazil |
| MAX | Ouro Sogui Airport | Ouro Sogui | 🇸🇳 Senegal |
| UVE | Ouvéa Airport | Ouvéa | 🇳🇨 New Caledonia |
| OYN | Ouyen Airport | Ouyen | 🇦🇺 Australia |
| KOZ | Ouzinkie Airport | Ouzinkie | 🇺🇸 United States |
| VDA | Ovda Airport | Eilat | 🇮🇱 Israel |
| OVG | Overberg Airport | Overberg | 🇿🇦 South Africa |
| FTX | Owando Airport | Owando | 🇨🇬 Congo - Brazzaville |
| OWA | Owatonna Degner Regional Airport | Owatonna | 🇺🇸 United States |
| GCM | Owen Roberts International Airport | George Town | 🇰🇾 Cayman Islands |
| YOS | Owen Sound / Billy Bishop Regional Airport | Owen Sound | 🇨🇦 Kanada |
| OWB | Owensboro Daviess County Airport | Owensboro | 🇺🇸 United States |
| YOH | Oxford House Airport | Oxford House | 🇨🇦 Kanada |
| OXR | Oxnard Airport | Oxnard | 🇺🇸 United States |
| OYE | Oyem Airport | Oyem | 🇬🇦 Gabon |
| OLL | Oyo Ollombo Airport | Oyo | 🇨🇬 Congo - Brazzaville |
| WMH | Ozark Regional Airport | Mountain Home | 🇺🇸 United States |
| OZA | Ozona Municipal Airport | Ozona | 🇺🇸 United States |