| 2601 | KKAH | KOLD KATCHER | | | SCAC4 |
| 2602 | KKAR | KELLEYS KARTAGE & EXPEDITING SERVIC | | | SCAC3 |
| 2603 | KKAT | K K & T INC | | | SCAC3 |
| 2604 | KKAT | K K & T INC | | | SCAC4 |
| 2605 | KKAW | KOYO KAIUN CO LTD | | | SCAC4 |
| 2606 | KKB | Air South, Inc. | Callsign: Khaki Blue, | USA | AVCODES |
| 2607 | KKB | Air South, Inc. | IATA: WV, | USA | AVCODES |
| 2608 | KKB | Air South | | | ICAO1 |
| 2609 | KKB | KKB s.r.o. | | CZ | VKM |
| 2610 | KKBC | K & K BROKERAGE LLC | | | SCAC4 |
| 2611 | KKBL | K & K BUS LINE | | | SCAC3 |
| 2612 | KKBU | KERNKRAFTWERK BRUNSBUTTEL GMBH & CO. OHG | | D | BIC |
| 2613 | KKCA | K K CARRIERS | | | SCAC4 |
| 2614 | KKCB | KLENKE CHARTER BUS SERVICE | | | SCAC3 |
| 2615 | KKCB | KILLORAN TRUCKING | | | SCAC4 |
| 2616 | KKCE | KKC EXPRESS CORP | | | SCAC4 |
| 2617 | KKCI | KOOLKAT CARRIERS INC | | | SCAC4 |
| 2618 | KKCL | KAMBARA KISEN CO., LTD. | | | SCAC3 |
| 2619 | KKCO | KELLY KONSOLIDATING COMPANY INC | | | SCAC3 |
| 2620 | KKCO | KURTS TRUCKING | | | SCAC4 |
| 2621 | KKCQ | KAISER KARTAGE CO | | | SCAC3 |
| 2622 | KKCR | KIRK CARRIERS LLC | | | SCAC4 |
| 2623 | KKCS | KENTS KORNER CONVENIENCE STORES | | | SCAC4 |
| 2624 | KKCW | KAMBARA KISEN CO LTD | | | SCAC4 |
| 2625 | KKCX | Glaser, Crandell Co. | 1/1946 (not listed) | | NAKINA |
| 2626 | KKCX | Keokuk Canning Co. | 7/1935-1/1945 | | NAKINA |
| 2627 | KKCX | Keokuk Canning Co. | Apr-38 | | NRHS |
| 2628 | KKCX | GLASER, CRANDELL CO. [KEOKUK CANNING CO.] | | | PWRC |
| 2629 | KKDE | KKD ENTERPRISES INC | | | SCAC3 |
| 2630 | KKDH | KRZESKI, K D HORSE TRANSPORTATION | | | SCAC3 |
| 2631 | KKDI | K & K DISTRIBUTION | | | SCAC3 |
| 2632 | KKES | KELLEY KARTAGE & EXPEDITING SERVICE | | | SCAC3 |
| 2633 | KKET | K & K ENTERPRISES AND TRUCKING LLC | | | SCAC4 |
| 2634 | KKEY | KELLY & KELLY ENTERPRISE LLC | | | SCAC4 |
| 2635 | KKFC | K K FARMS LLC | | | SCAC4 |
| 2636 | KKFG | KUSMENKO KUSTOM FARMING | | | SCAC4 |
| 2637 | KKFL | KROEKER FARMS LIMITED | | | SCAC4 |
| 2638 | KKFU | KAWASAKI KISEN KAISHA LTD - K LINE | | J | BIC |
| 2639 | KKFU | KAWASAKI KISEN KAISHA LTD | | | SCAC4 |
| 2640 | KKFW | K & K FORWARDING (2008) LTD | | | SCAC4 |
| 2641 | KKGC | KARAS & KARAS GLASS CO INC | | | SCAC4 |
| 2642 | KKGE | KOOL KING EXPRESS INC | | | SCAC4 |
| 2643 | KKGI | KK GROUP TRANSPORT INC | | | SCAC4 |
| 2644 | KKHU | KANI KOMMERZ GMBH | | | SCAC3 |
| 2645 | KKIP | KWIK KARGO INC TRANSPORT | | | SCAC4 |
| 2646 | KKIT | KWIK KARGO INC TRUCKING | | | SCAC4 |
| 2647 | KKJF | KURDZIONAK, JOHN F | | | SCAC4 |
| 2648 | KKK | Atlasjet Uuslararasi Havacilik A/S | IATA: KK, Callsign: Atlasjet, IATA Prefix: 610, ICAO designator changed from OGE . IATA designator changed from 2U*. Name changed from Atlas International Airlines - Atlas International Havacilik A/S | TR | AVCODES |
| 2649 | KKK | Atlasjet Airlines Inc | IATA: KK, Callsign: Atlasjet, IATA Prefix: 610, Name changed to AtlasGlobal Airlines. Name changed from Atlas International Airlines - Atlas International Havacilik A/S. ICAO designator changed from OGE . IATA designator changed from 2U* | TR | AVCODES |
| 2650 | KKK | AtlasGlobal Airlines | IATA: KK, Callsign: Atlasjet, IATA Prefix: 610, Ceased operations on 12 February 2020. Name changed from Atlasjet Airlines Inc. Name changed from Atlas International Airlines - Atlas International Havacilik A/S. ICAO designator changed from OGE . IATA designator changed from 2U* | TR | AVCODES |
| 2651 | KKK | Atlasjet | IATA: KK | | ICAO1 |
| 2652 | KKKU | OZTURK KONTEYNER SAN VE TIC LTD STI | | TR | BIC |
| 2653 | KKKU | TURKISH ARMY STAFF | | | SCAC4 |
| 2654 | KKL | Kol-Kol Airlines Ltd. | Callsign: Kolkol Air, | WAN | AVCODES |
| 2655 | KKLA | K & K LOGISTICS LLC | | | SCAC4 |
| 2656 | KKLC | KOOL KARRIERS LLC | | | SCAC4 |
| 2657 | KKLI | KING KONG LOGISTICS INC | | | SCAC4 |
| 2658 | KKLL | KIRK LINE LIMITED | | | SCAC3 |
| 2659 | KKLM | KEMP, K LOGISTICS LLC | | | SCAC4 |
| 2660 | KKLO | KRIKELO SHIPPING S A | | | SCAC4 |
| 2661 | KKLT | KOUNKEL TRUCKING LLC | | | SCAC4 |
| 2662 | KKLU | KAWASAKI KISEN KAISHA LTD - K LINE | | J | BIC |
| 2663 | KKLU | K LINE | | | PWRC |
| 2664 | KKLU | K Line | | | RSRV |
| 2665 | KKLU | K LINE (KAWASAKI KISEN KAISHA LTD) | | | SCAC3 |
| 2666 | KKLU | KAWASAKI KISEN KAISHA LTD | | | SCAC4 |
| 2667 | KKLZ | K LINE | | | PWRC |
| 2668 | KKLZ | K Line | | | RSRV |
| 2669 | KKLZ | K LINE | | | SCAC4 |
| 2670 | KKMH | K & K MOBILE HOMES INC | | | SCAC3 |
| 2671 | KKMJ | KITTRICK, MICHAEL J | | | SCAC3 |
| 2672 | KKMN | KIRKMAN TRUCKING, INC | | | SCAC3 |
| 2673 | KKMV | K & K MOVING | | | SCAC3 |
| 2674 | KKMZ | KOKOMO RANGE | | | PWRC |
| 2675 | KKNA | KAUKAUNA MEATS INC | | | SCAC4 |
| 2676 | KKON | K KONCRETE INC (AN ILLINOIS CORP) | | | SCAC3 |
| 2677 | KKPC | KLEIN KOSHER PICKEL COMPANY INC | | | SCAC4 |
| 2678 | KKPS | KKP TRANSPORTATION SERVICES LTD | | | SCAC4 |
| 2679 | KKPT | KIRKPATRICK SHIPPING INC. | | | SCAC3 |
| 2680 | KKRE | K & K EXPRESS SERVICE INC | | | SCAC4 |
| 2681 | KKRR | Knox & Kane R.R. Co. | added 10/1982; 1/1994-7/2005; eliminated 10/2006 | | NAKINA |
| 2682 | KKRR | Knox & Kane R.R. Co. | added 10/82; 1/94-7/2000 | | NRHS |
| 2683 | KKRR | KNOX & KANE RAILROAD COMPANY | | | PWRC |
| 2684 | KKRR | Knox and Kane Railroad | | | RSRV |
| 2685 | KKRR | KNOX & KANE RAILROAD COMPANY | | | SCAC3 |
| 2686 | KKRS | KUSTOM KARRIERS LLC | | | SCAC4 |
| 2687 | KKRV | K & K RECYCLING SERVICES | | | SCAC4 |
| 2688 | KKRX | KASKASKIA REGIONAL PORT DISTRICT RAILROAD | | | PWRC |
| 2689 | KKRX | Kaskaskia Regional Port District Railroad | | | RSRV |
| 2690 | KKS | Salem | Callsign: Kokshe, | KZ | AVCODES |
| 2691 | KKS | Salem | | | ICAO1 |
| 2692 | KKSC | KOKOSING CONSTRUCTION CO INC | | | SCAC4 |
| 2693 | KKSG | K & K SCHIFFAHRT GERMANY | | | SCAC4 |
| 2694 | KKSS | KODIAK SHELTER SYSTEMS | | | SCAC4 |
| 2695 | KKST | KILLEEN, KITTY & SONS TRANSPORTATIO | | | SCAC3 |
| 2696 | KKSTB | Kaiserliche-Königliche Staatsbahnen ? | | A | TRAFFIC |
| 2697 | KKTA | KENT KARTAGE, INC | | | SCAC3 |
| 2698 | KKTB | K & K TRUCKING (AIR FREIGHT EXPRESS | | | SCAC3 |
| 2699 | KKTB | K/K TRANSPORTATION LLC | | | SCAC4 |
| 2700 | KKTE | KIRK TRUCKING SERVICE INC | | | SCAC4 |
