| 1 | KAP | Cape Air | IATA: 9K, Callsign: Cair, Name changed to Hyannis Air Service, Inc. | USA | AVCODES |
| 2 | KAP | Hyannis Air Service, Inc. d/b/a Cape Air | IATA: 9K, Callsign: Cair, Name changed from Cape Air | USA | AVCODES |
| 3 | KAP | Cape Air | IATA: 9K | | ICAO1 |
| 4 | KAP | Kapos Volán | Part of the Keisei Electric Railway | H | TRAFFIC |
| 5 | KAPA | KAPLAN ENTERPRISES INC | | | SCAC3 |
| 6 | KAPA | KAPAY, CLARENCE | | | SCAC4 |
| 7 | KAPB | KAPPERM | | | SCAC4 |
| 8 | KAPC | K & P TRUCKING CO | | | SCAC3 |
| 9 | KAPC | K & P TRUCKING LLC | | | SCAC4 |
| 10 | KAPD | K & P DELIVERY | | | SCAC3 |
| 11 | KAPE | KAMPMANN ELEVATOR INC | | | SCAC3 |
| 12 | KAPI | KAP INC | | | SCAC3 |
| 13 | KAPK | Kaposvári Kisvasút | | H | TRAFFIC |
| 14 | KAPL | KAPLAN LUMBER CO | | | SCAC3 |
| 15 | KAPM | KAPMEY | | | SCAC4 |
| 16 | KAPO | KAPOWSIN MEATS INC | | | SCAC4 |
| 17 | KAPP | KAPITAL PRODUCE (2006) LTD | | | SCAC4 |
| 18 | KAPR | KAPP, RYAN | | | SCAC4 |
| 19 | KAPT | KAPS TRANSPORT LTD | | | SCAC3 |
| 20 | KAPU | KOMATSU AMERICA CORP | | USA | BIC |
| 21 | KAPU | Northland Seasonal Storage | | | RSRV |
| 22 | KAPU | NORTHLAND SEASONAL STORAGE | | | SCAC4 |
| 23 | KAPV | Kaposvári Városi Közlekedés | City: Kaposvár | H | TRAFFIC |
| 24 | KAPX | K.A. Powell (Canada) Ltd. | added 10/1953; 7/1954-10/1957; eliminated 7/1958 | | NAKINA |
| 25 | KAPX | K.A. Powell (Canada) Ltd. | added 10/53; 10/57; eliminated 7/58 | | NRHS |
| 26 | KAPX | K. A. POWELL (CANADA) LTD. | | | PWRC |
