| IATA | ICAO | Airline | Call sign | Country | Comments |
|---|---|---|---|---|---|
| AOE | Livingstone Executive | LIVINGSTONE AIR | Italy | ||
| LZF | Lease Fly | SKYLEASE | Portugal | ||
| LHB | Liebherr Geschaeftreiseflugzeug | FAMILY | Germany | ||
| LLD | Lloyd Aviation | Venezuela | |||
| LGA | Logistic Air | LOGAIR | Malaysia | ||
| LGC | Legacy Air | LEGACY AIR | Thailand | ||
| JKA | LeTourneau University | JACKET | United States | ||
| LTY | Liberty Air | SKYDECK | Netherlands | ||
| LWL | Lowlevel | CUB DRIVER | Portugal | ||
| LAX | Laminar Air | Spain | |||
| YL | LWA | Libyan Wings | LIBYAN WINGS | Libya | |
| YQ | LCT | TAR Aerolineas | TAR | Mexico | |
| LAH | L A Helicopter | STAR SHIP | United States | ||
| LJY | L J Aviation | ELJAY | United States | ||
| LRB | L R Airlines | LADY RACINE | Czech Republic | ||
| PHO | L&L Flygbildteknik | PHOTOFLIGHT | Sweden | ||
| LEX | L'Express Airlines | LEX | United States | ||
| FNT | L-3 Communications Flight International Aviation | FLIGHT INTERNATIONAL | United States | ||
| JF | LAB | L.A.B. Flying Service | LAB | United States | |
| LR | LRC | LACSA | LACSA | Costa Rica | |
| LDE | LADE - Líneas Aéreas Del Estado | LADE | Argentina | ||
| KG | BNX | LAI - Línea Aérea IAACA | AIR BARINAS | Venezuela | |
| 4M | DSM | LATAM Argentina | LAN AR | Argentina | |
| JJ | TAM | LATAM Brasil | TAM | Brazil | |
| UC | LCO | LATAM Cargo Chile | LAN CARGO | Chile | |
| LA | LAN | LATAM Chile | LAN CHILE | Chile | |
| 4C | ARE | LATAM Colombia | LAN COLOMBIA | Colombia | |
| LNC | LAN Dominicana | LANCANA | Dominican Republic | ||
| LU | LXP | LATAM Express | LANEX | Chile | |
| PZ | LAP | LATAM Paraguay | PARAGUAYA | Paraguay | |
| LP | LPE | LATAM Peru | LANPERU | Peru | |
| NI | LANICA | Nicaragua | |||
| LSA | LANSA | INTERNACIONAL | Dominican Republic | ||
| APT | LAP Colombia - Líneas Aéreas Petroleras, S.A. | LAP | Colombia | ||
| LCB | LC Busre | BUSRE | Peru | ||
| L5 | Línea Aérea Cuencana | Ecuador | |||
| LO | LOT | LOT Polish Airlines | POLLOT | Poland | "POLLOT" is not used in practice. "LOT" is used in almost all cases. |
| JKA | LeTourneau University | JACKET | United States | ||
| XO | LTE | LTE International Airways | FUN JET | Spain | |
| L3 | LTO | LTU Austria | BILLA TRANSPORT | Austria | |
| LT | LTU | LTU International | LTU | Germany | |
| JFC | LTV Jet Fleet Corporation | JET-FLEET | United States | ||
| LUK | LUKoil-Avia | LUKOIL | Russia | ||
| ASK | La Ronge Aviation Services | AIR SASK | Canada | ||
| LVT | La Valenciana Taxi Aéreo | TAXIVALENCIANA | Mexico | ||
| SKQ | Labcorp | SKYLAB | United States | ||
| LAL | Labrador Airways | LAB AIR | Canada | ||
| N6 | JEV | Lagun Air | Spain | ||
| HCA | Lake Havasu Air Service | HAVASU | United States | ||
| LKL | Lakeland Aviation | LAKELAND | United States | ||
| LKR | Laker Airways | LAKER | United States | ||
| LBH | Laker Airways (Bahamas) | LAKER BAHAMAS | United States | ||
| LMR | Lamra | LAMAIR | Sudan | ||
| TCR | Lanaes Aereas Trans Costa Rica | TICOS | Costa Rica | ||
| ISL | Landsflug | ISLANDIA | Iceland | ||
| PAP | Langtry Flying Group | PROFLIGHT | United Kingdom | ||
| IK | LKN | Lankair | Lankair | Sri Lanka | |
| QL | RLN | Lankan Cargo | AERO LANKA | Sri Lanka | |
| LZA | Lanza Air | AEROLANZA | Spain | ||
| LZT | Lanzarote Aerocargo | BARAKA | Spain | ||
| QV | LAO | Lao Airlines | LAO | Lao People's Democratic Republic | |
| LKA | Lao Capricorn Air | NAKLAO | Lao People's Democratic Republic | ||
| LLL | Lao Skyway | LAVIE | Lao People's Democratic Republic | ||
| L7 | LPN | Laoag International Airlines | LAOAG AIR | Philippines | |
| LRD | Laredo Air | LAREDO AIR | United States | ||
| OTN | LASTP | LASTP | São Tomé and Príncipe | ||
| LTC | LatCharter | LATCHARTER | Latvia | defunct | |
| LAF | Latvian Air Force | LATVIAN AIRFORCE | Latvia | ||
| NG | LDA | Lauda Air | LAUDA AIR | Austria | |
| OE[1] | LDM | LaudaMotion | LAUDA MOTION | Austria | |
| LDI | Lauda Air Italy | LAUDA ITALY | Italy | ||
| LEP | Laughlin Express | LAUGHLIN EXPRESS | United States | ||
| LSU | Laus | LAUS AIR | Croatia | ||
| LAR | Lawrence Aviation | LAWRENCE | United States | ||
| LAY | Layang-Layang Aerospace | LAYANG | Malaysia | ||
| LPL | Lease-a-Plane International | LEASE-A-PLANE | United States | ||
| LQ | LAQ | Lebanese Air Transport | LAT | Lebanon | |
| LAT | Lebanese Air Transport (charter) | LEBANESE AIR | Lebanon | ||
| LAD | Lebanon Airport Development Corporation | LADCO-AIR | United States | ||
| LEB | Lebap | LEBAP | Turkmenistan | ||
| LCA | Leconte Airlines | LECONTE | United States | ||
| LI | LIA | Leeward Islands Air Transport | LIAT | Antigua and Barbuda | |
| LGD | Legend Airlines | LEGENDARY | United States | ||
| LWD | Leisure Air | LEISURE WORLD | United States | ||
| LEN | Lentini Aviation | LENTINI | United States | ||
| LOR | Leo-Air | LEO CHARTER | South Africa | ||
| LEL | Leonsa De Aviación | LEONAVIA | Spain | ||
| LV | LVL | Level | LEVEL | Spain and France | |
| LYW | Libyan Airlines | LIBYAN AIRWAYS | Libya | ||
| LN | LAA | Libyan Arab Airlines | LIBAIR | Libya | |
| LCR | Libyan Arab Air Cargo | LIBAC | Libya | ||
| LIQ | Lid Air | Sweden | |||
| LTA | LIFT Academy | LIFT | United States | ||
| LCG | Lignes Aeriennes Congolaises | CONGOLAISE | Democratic Republic of the Congo | ||
| LKD | Lignes Aeriennes Du Tchad | LATCHAD | Chad | ||
| LME | Lignes Mauritaniennes Air Express | LIMAIR EXPRESS | Mauritania | ||
| GCB | Lignes Nationales Aeriennes - Linacongo | LINACONGO | Republic of the Congo | ||
| GDQ | Lincoln Air National Guard | United States | |||
| LRT | Lincoln Airlines | Australia | |||
| LSY | Lindsay Aviation | LINDSAY AIR | United States | ||
| NOT | Línea Aérea Costa Norte | COSTA NORTE | Chile | ||
| LMC | Línea Aérea Mexicana de Carga | LINEAS DECARGA | Mexico | ||
| L7 | LNP | Línea Aérea SAPSA | SAPSA | Chile | |
| NEG | Línea Aérea de Fumig Aguas Negras | AGUAS NEGRAS | Chile | ||
| QL | LER | Línea Aérea de Servicio Ejecutivo Regional | LASER | Venezuela | |
| LSE | Línea De Aeroservicios | Chile | |||
| TUY | Línea Turística Aereotuy | AEREOTUY | Venezuela | ||
| ALR | Líneas Aéreas Alaire S.L. | AEROLAIRE | Spain | ||
| ZE | LCD | Líneas Aéreas Azteca | LINEAS AZTECA | Mexico | defunct |
| LCN | Líneas Aéreas Canedo LAC | CANEDO | Bolivia | ||
| LCM | Líneas Aéreas Comerciales | LINEAS COMERCIALES | Mexico | ||
| EDD | Líneas Aéreas Ejectuivas De Durango | LINEAS DURANGO | Mexico | ||
| EDR | Líneas Aéreas Eldorado | ELDORADRO | Colombia | ||
| FED | Líneas Aéreas Federales | FEDERALES | Argentina | ||
| LMN | Líneas Aéreas Monarca | LINEAS MONARCA | Mexico | ||
| LIJ | Líneas Aéreas San Jose | LINEAS JOSE | Mexico | ||
| UMA | Líneas Aéreas del Humaya | HUMAYA | Mexico | ||
| LEC | Linex | LECA | Central African Republic | ||
| SMS | Linhas Aéreas Santomenses | SANTOMENSES | São Tomé and Príncipe | ||
| TM | LAM | Linhas Aéreas de Moçambique | MOZAMBIQUE | Mozambique | |
| LAW | Link Airways of Australia | Australia | |||
| WGT | Volkswagen AirService GmbH | WORLDGATE | United Kingdom | ||
| JT | LNI | Lion Air | LION INTER | Indonesia | |
| LEU | Lions-Air | LIONSAIR | Switzerland | ||
| LYF | Lithuanian Air Force | LITHUANIAN AIRFORCE | Lithuania | safety department | |
| LRA | Little Red Air Service | LITTLE RED | Canada | ||
| LM | LVG | Livingston Energy Flight | LIVINGSTON | Italy | Ceased operations 2010 |
| LT | SNG | LJ Air | SNOW EAGLE | China | |
| LB | LLB | Lloyd Aéreo Boliviano | LLOYDAEREO | Bolivia | |
| LNA | Lnair Air Services | ELNAIR | Spain | ||
| XLG | Lockheed Air Terminal | United States | |||
| LAC | Lockeed Aircraft Corporation | LOCKHEED | United States | ||
| XDD | Lockheed DUATS | United States | |||
| CBD | Lockheed Martin Aeronautics | CATBIRD | United States | ||
| LNG | Lockheed Martin Aeronautics Company | LIGHTNING | United States | ||
| LM | LOG | Loganair | LOGAN | United Kingdom | Gained the code LM after beginning independent operations (2017) |
| CLV | Lom Praha Flying School | AEROTRAINING | Czech Republic | ||
| LMS | Lomas Helicopters | LOMAS | United Kingdom | ||
| LCY | London City Airport Jet Centre | LONDON CITY | United Kingdom | ||
| LNX | London Executive Aviation | LONEX | United Kingdom | ||
| LOV | London Flight Centre (Stansted) | LOVEAIR | United Kingdom | ||
| LHC | London Helicopter Centres | MUSTANG | United Kingdom | ||
| LSS | Lone Star Airlines | LONE STAR | United States | ||
| ORA | Long Island Airlines | LONG ISLAND | United States | ||
| GI | LHA | Longhao Airlines | AIR CANTON | China | |
| LGT | Longtail Aviation | LONGTAIL | Bermuda | ||
| GJ | CDC | Loong Air | LOONG AIR | China | |
| LRR | Lorraine Aviation | LORRAINE | France | ||
| LSC | Los Cedros Aviación | CEDROS | Chile | ||
| TAS | Lotus Air | LOTUS FLOWER | Egypt | ||
| LTW | Luchtvaartmaatschappij Twente | TWENTAIR | Netherlands | ||
| LKE | Lucky Air | LUCKY AIR | China | ||
| LUT | Luft Carago | LUGO | South Africa | ||
| LVD | Luftfahrt-Vermietungs-Dienst | AIR SANTE | Austria | ||
| LH | DLH | Lufthansa | LUFTHANSA | Germany | |
| LH | GEC | Lufthansa Cargo | LUFTHANSA CARGO | Germany | |
| CL | CLH | Lufthansa CityLine | HANSALINE | Germany | |
| L1 | Lufthansa Systems | Germany | |||
| LHT | Lufthansa Technik | LUFTHANSA TECHNIK | Germany | ||
| LTF | Lufttaxi Fluggesellschaft | Garfield | Germany | ||
| L5 | LTR | Lufttransport | LUFT TRANSPORT | Norway | |
| LHS | Luhansk | ENTERPRISE LUHANSK | Ukraine | ||
| UNY | Lund University School of Aviation | UNIVERSITY | Sweden | ||
| LG | LGL | Luxair | LUXAIR | Luxembourg | |
| LXA | Luxaviation | RED LION | Luxembourg | ||
| LUV | Luxembourg Air Rescue | LUX RESCUE | Luxembourg | ||
| LFE | Luxflight Executive | LUX EXPRESS | Luxembourg | ||
| LXO | Luxor Air | Egypt | |||
| LUZ | Luzair | LISBON JET | Portugal | ||
| 5V | UKW | Lviv Airlines | UKRAINE WEST | Ukraine | |
| LYD | Lydd Air | LYDDAIR | United Kingdom | ||
| LCH | Lynch Flying Service | LYNCH AIR | United States | ||
| L2 | LYC | Lynden Air Cargo | LYNDEN | United States | |
| LWG | Luxwing | LUXWING | Malta | ||
| Y9 | DAT | Lynx Air | DAUNTLESS | Canada | |
| LXF | Lynx Air International | LYNX FLIGHT | United States | ||
| L4 | SSX | Lynx Aviation | SHASTA | United States | Part of Frontier Airlines |
| LYX | Lynx Aviation | LYNX AIR | Pakistan | ||
| Z8 | AZN | Línea Aérea Amaszonas | Bolivia | ||
| MJ | LPR | Líneas Aéreas Privadas Argentinas | LAPA | Argentina | defunct |
| LAU | Líneas Aéreas Suramericanas | SURAMERICANO | Colombia | ||
| LT | SNG | LongJiang Airlines | SNOW EAGLE | China | |
| LYB | Lynden Air Cargo | HIGHLANDS | Papua New Guinea | ||