| 1 | KA | Hong Kong Dragon Airlines Limited t/a Dragonair | ICAO: HDA, Callsign: Dragonair, IATA Prefix: 043, ICAO callsign changed to Dragon | HK | AVCODES |
| 2 | KA | Kalinga Airlines | | IND | AVCODES |
| 3 | KA | Hong Kong Dragon Airlines Limited t/a Dragonair | ICAO: HDA, Callsign: Dragon, IATA Prefix: 043, ICAO callsign changed from Dragonair. Name changed to Hong Kong Dragon Airlines Limited t/a Cathay Dragon. | HK | AVCODES |
| 4 | KA | Airbusiness A/S | ICAO: ABZ, Callsign: Airbiz, | DK | AVCODES |
| 5 | KA | Hong Kong Dragon Airlines Limited t/a Cathay Dragon | ICAO: HDA, Callsign: Dragon, IATA Prefix: 043, Founded on 24 May 1985. Commenced operations in July 1985. Ceased operations on 21 October 2020. ICAO callsign changed from Dragonair . Name changed from Hong Kong Dragon Airlines Limited t/a Dragonair. | HK | AVCODES |
| 6 | KA | Aero Nomad Airlines, LLC | ICAO: ANK, Callsign: Aero Nomad, | KS | AVCODES |
| 7 | KA | Franz Kassecker GmbH | | DE | VKM |
| 8 | KAA | Asia Aero Survey And Consulting Engineers, Inc. | Callsign: Aasco, | ROK | AVCODES |
| 9 | KAA | Asia Aero Survey and Consulting Engineers | | | ICAO1 |
| 10 | KAABS | Kaabs Nordic AB | | SE | VKM |
| 11 | KAAD | KANADA CARRIERS | | | SCAC3 |
| 12 | KAAK | KAAKE TRUCKING COMPANY | | | SCAC3 |
| 13 | KAAL | KAALBYE SHIPPING UKRAINE | | | SCAC4 |
| 14 | KAAN | K A TRUCKING COMPANY | | | SCAC3 |
| 15 | KAAN | KRUSNIAK, ANTHONY | | | SCAC4 |
| 16 | KAAQ | KLECKER AND ANDERSON | | | SCAC3 |
| 17 | KAAR | KALITTA AIR LLC | | | SCAC4 |
| 18 | KAB | Aviabaltika | Callsign: Aviabaltika, | LT | AVCODES |
| 19 | KAB | Air Pohang Co., Ltd. | IATA: RN, Callsign: Air Pohang, Commenced operations on 07 February 2018. Ceased operations on 29 November 2018. | ROK | AVCODES |
| 20 | KABA | K A BAIT LTD | | | SCAC4 |
| 21 | KABB | KAB-8 INC | | | SCAC4 |
| 22 | KABD | KAIBAB DISTRIBUTION CORPOORTATION | | | SCAC3 |
| 23 | KABG | KAMLOOPS AUGERING & BORING LTD | | | SCAC4 |
| 24 | KABH | KALBACH, C H TRUCKING | | | SCAC3 |
| 25 | KABI | KAIBAB TRANSPORTATION INC | | | SCAC3 |
| 26 | KABI | KABAILCO INC | | | SCAC4 |
| 27 | KABL | KABLE BROTHERS TRANSPORT | | | SCAC3 |
| 28 | KABM | KORTSCH, A B C MOVING & STORAGE INC | | | SCAC3 |
| 29 | KABM | KAPA LOGISTICS LTD | | | SCAC4 |
| 30 | KABO | KABECO INC | | | SCAC3 |
| 31 | KABO | KAILE7 TRANSPORT INC | | | SCAC4 |
| 32 | KABQ | KABBES TURCKING | | | SCAC3 |
| 33 | KABQ | KCLA TRANSPORTATION | | | SCAC4 |
| 34 | KABR | K AND B TRANSPORTATION LLC | | | SCAC4 |
| 35 | KABX | Canadian Resource Distribution Inc. | 7/2000-7/2005 (not listed) | | NAKINA |
| 36 | KABX | Kaber Co. | 1/1994 (not listed) | | NAKINA |
| 37 | KABX | Bay State Milling Co. | eliminated 10/1993 | | NAKINA |
| 38 | KABX | Kaber Co. | 1/1975; added 4/1975; 1/1980; eliminated 7/1993 | | NAKINA |
| 39 | KABX | Kaber Co. | 1/75; added 4/75; 1/80; eliminated 7/93 | | NRHS |
| 40 | KABX | Bay State Milling Co. | eliminated 10/93 | | NRHS |
| 41 | KABX | Kaber Co. | Jan-94 | | NRHS |
| 42 | KABX | Canadian Resource Distribution Inc. | Jul-00 | | NRHS |
| 43 | KABX | *RETIRED 08-25-93 ATP [BAY STATE MILLING; kABER CO.] | | | PWRC |
| 44 | KABX | +CANADIAN RESOURCE DISTRIBUTION INC | | | PWRC |
| 45 | KABX | Kaber Canadian Resource Distribution | | | RSRV |
| 46 | KABX | CANADIAN RESOURCE DISTRIBUTION INC | | | SCAC4 |
| 47 | KAC | Kuwait Airways | IATA: KU, Callsign: Kuwaiti, IATA Prefix: 229, ICAO designator changed from Kilo Uniform. | KWT | AVCODES |
| 48 | KAC | Kuwait Airways | IATA: KU, Callsign: Kilo Uniform, IATA Prefix: 229, ICAO designator changed to Kuwaiti | KWT | AVCODES |
| 49 | KAC | Kuwait Airways | IATA: KU | | ICAO1 |
| 50 | KAC | Kuwait Airways | | KWT | TRAFFIC |
| 51 | KACA | A-KALALA TRANSPORT LTD | | | SCAC4 |
| 52 | KACE | KATH, CARL E JR | | | SCAC3 |
| 53 | KACF | K & C FREIGHTWAYS INC | | | SCAC3 |
| 54 | KACG | K & C GRAIN | | | SCAC3 |
| 55 | KACH | KAISER CHEMICALS | | | PWRC |
| 56 | KACH | KACHINA TRANSPORTATION | | | SCAC3 |
| 57 | KACH | KACHAN, RANDY | | | SCAC4 |
| 58 | KACI | KARON CARRIER INC | | | SCAC3 |
| 59 | KACL | KACE LOGISTICS INC | | | SCAC4 |
| 60 | KACN | KANSAS AIR CENTER INC | | | SCAC4 |
| 61 | KACR | KACH TRANSPORTATION | | | SCAC3 |
| 62 | KACR | KACH TRANSPORTATION INC | | | SCAC4 |
| 63 | KACT | K & C TRUCKING CO INC | | | SCAC3 |
| 64 | KACT | K & C TRUCKING CO INC | | | SCAC4 |
| 65 | KACU | CASPIAN CONTAINER LINE LLC | | | SCAC4 |
| 66 | KACV | KACHARAVA SHIPPING COMPANY LTD | | | SCAC3 |
| 67 | KACV | K T TRANSPORTATION | | | SCAC4 |
| 68 | KACX | Kaiser Aluminum & Chemical Corp. | added 4/1959; 4/1961-1/1994; eliminated 7/1994; 7/2000-7/2005 (not listed) | | NAKINA |
| 69 | KACX | Kaiser Aluminum & Chemical Corp. | 4/61-1/94; eliminated 7/94; 7/2000 | | NRHS |
| 70 | KACX | KAISER ALUMINUM & CHEMICAL CORP. | | | PWRC |
| 71 | KACX | Kaiser Aluminum and Chemical Corporation | | | RSRV |
| 72 | KACX | KAISER ALUMINUM & CHEMICAL CORP | | | SCAC3 |
| 73 | KACX | KAISER ALUMINUM & CHEMICAL CORP | | | SCAC4 |
| 74 | KACY | KELLER, ALLEN COMPANY | | | SCAC4 |
| 75 | KAD | Air Kirovograd Compania Airlines | Callsign: Air Kirvovgrad, Name changed to Aerolux Air Company | UA | AVCODES |
| 76 | KAD | Aerolux Air Company | Callsign: Air Kirvovgrad, Ceased operations in 2010. Name changed from Air Kirovograd Compania Airlines | UA | AVCODES |
| 77 | KAD | Air Kirovograd | | | ICAO1 |
| 78 | KADC | K & D TRUCKING COMPANY LTD | | | SCAC3 |
| 79 | KADE | KADER TRANSPORT | | | SCAC4 |
| 80 | KADL | KARDELL LEASING CO | | | SCAC3 |
| 81 | KADL | KANES DISTRIBUTING LIMITED | | | SCAC4 |
| 82 | KADN | KA DON ENTERPRISE LTD | | | SCAC3 |
| 83 | KADQ | K AND D TRUCKLINES | | | SCAC3 |
| 84 | KADR | KADER COMPANY INC | | | SCAC3 |
| 85 | KAE | Kartika Airlines, PT. | IATA: 3Y, Callsign: Kartika, Founded in 2001. Commenced operations on 15 May 2001. Ceased operations in 2010. | RI | AVCODES |
| 86 | KAE | Kartika Airlines | | | ICAO1 |
| 87 | KAEI | K & A EXPRESS INC | | | SCAC4 |
| 88 | KAEJ | KANE FREIGHT LINES INC | | | SCAC3 |
| 89 | KAEJ | KANE FREIGHT LINES INC | | | SCAC4 |
| 90 | KAEM | K & E MOVING & STORAGE | | | SCAC3 |
| 91 | KAEP | KLASS ACT EXPRESS | | | SCAC4 |
| 92 | KAET | KAETS TRANSPORT INC | | | SCAC3 |
| 93 | KAF | Kafue International Air Services Limited | | Z | AVCODES |
| 94 | KAF | Kyrgyz Air | IATA: KT, Callsign: Ak Shoumkar, Designator KT recalled by IATA | KS | AVCODES |
| 95 | KAF | Kyrgyz Air | Callsign: Ak Shoumkar, Designator KT recalled by IATA | KS | AVCODES |
| 96 | KAF | KAF Falkenhahn Bau AG | | DE | VKM |
| 97 | KAFB | KAFKA BROS, INC | | | SCAC3 |
| 98 | KAFC | KAFCO DE MEXICO SA DE CV | | | SCAC4 |
| 99 | KAFF | KAUFFMAN, JAMES M | | | SCAC3 |
| 100 | KAFL | KNIGHTS APPLEDEN FRUIT LIMITED | | | SCAC4 |
