| 4401 | KQTI | K T I | | | SCAC4 |
| 4402 | KQTU | KEIKU CO., LTD. | | RC | BIC |
| 4403 | KR | Kitty Hawk Aircargo, Inc. | {`ICAO: KHA, Callsign: Air Kittyhawwk, IATA Prefix: 798, Founded in 1976 as Kitty Hawk Airways). Commenced operations in 1985. Ceased operations in 2008. Name changed from Kitty Hawk Air Cargo, Inc.`};SRCKEY=AVCODES | USA | |
| 4404 | KR | Kitty Hawk Air Cargo, Inc. | ICAO: KHA, Callsign: Air Kittyhawwk, IATA Prefix: 798, Name changed to Kitty Hawk Aircargo, Inc. | USA | AVCODES |
| 4405 | KR | Kar-Air O/Y | ICAO: KAR, Callsign: Karair, Designator KR recalled by IATA. Merged into Finnair | FIN | AVCODES |
| 4406 | KR | Aviation Company MDA | IATA designator changed from EV* | RUS | AVCODES |
| 4407 | KR | Comores Aviation | ICAO: KMZ, | COM | AVCODES |
| 4408 | KR | Aliblu Airways S.p.A. | ICAO: KRO, Callsign: Alibly, | I | AVCODES |
| 4409 | KR | Air Bishkek Aircompany d/b/a Air Bishkek Ltd. | ICAO: EAA, Callsign: Eastok, IATA Prefix: 265, Ceased operations in February 2016. Name changed from Kyrgyz Airways d/b/a Kyrgyz Airways Ltd. Air Company. Name changed from Eastok Avia. | KS | AVCODES |
| 4410 | KR | Cambodia Airways Co., Ltd. | ICAO: KME, Callsign: Giant Ibis, Commence operations on 10 July 2018. | K | AVCODES |
| 4411 | KR | Kenya National Railway | | EAK | TRAFFIC |
| 4412 | KRA | Krial-Air, Joint-Stock Air Company | Callsign: Marat, | RUS | AVCODES |
| 4413 | KRA | Transcontinental Airlines, CJSC | Callsign: Regata, | KZ | AVCODES |
| 4414 | KRA | Arkas S.A. | Founded in 2007. Ceased operations during 2011. | CO | AVCODES |
| 4415 | KRA | Kraken Air | Callsign: Kraken, | GB | AVCODES |
| 4416 | KRA | Transcontinental Airlines | | | ICAO1 |
| 4417 | KRAB | KRAMER BROS, FREIGHT LINES, INC | | | SCAC3 |
| 4418 | KRAB | KRONA ENTERPRISES LTD | | | SCAC4 |
| 4419 | KRAE | KRAUS, FREDERICK TRUCKING | | | SCAC3 |
| 4420 | KRAE | KROGER DEDICATED LOGISTICS GROUP | | | SCAC4 |
| 4421 | KRAJ | KRAJACK TANK LINES INC | | | SCAC3 |
| 4422 | KRAK | KRASK BROTHERS VAN LINES, INC | | | SCAC3 |
| 4423 | KRAK | KRAKOWSKI TRUCKING INC | | | SCAC4 |
| 4424 | KRAK | | Real: MPK, City: Krakow | PL | TRAFFIC |
| 4425 | KRAM | KRAM, PAT TRUCKING | | | SCAC4 |
| 4426 | KRAPF | Krapf's | | US-PA | TRAFFIC |
| 4427 | KRAR | KRASNER, BROCK TRUCKING | | | SCAC3 |
| 4428 | KRAR | KRAMERS INC | | | SCAC4 |
| 4429 | KRAS | NAGORSK SHIPPING CO. LTD. | | | SCAC3 |
| 4430 | KRB | Karibu Airways Company | Callsign: Karibu Air, | EAT | AVCODES |
| 4431 | KRB | Karibu Airways Company | | | ICAO1 |
| 4432 | KRB | Køge - Ringsted Banen | 1917 - 1963 | DK | jernbanen.dk |
| 4433 | KRB | Koge - Ringsted Banen | 1917 - 1963 | DK | TRAFFIC |
| 4434 | KRBA | KELLYS ROLL-BACK SERVICE INC | | | SCAC3 |
| 4435 | KRBA | KRISRO METAL INDUSTRIES LIMITED | | | SCAC4 |
| 4436 | KRBB | KRB INTERMODAL INC | | | SCAC4 |
| 4437 | KRBG | KIRBYS GARAGE INC | | | SCAC4 |
| 4438 | KRBI | KEENE ROADBUILDERS INC | | | SCAC3 |
| 4439 | KRBI | KRYSTAL LOGISTICS USA INC | | | SCAC4 |
| 4440 | KRBJ | KIRKPATRICK, BILLY J | | | SCAC3 |
| 4441 | KRBK | K M CARRIER INC | | | SCAC4 |
| 4442 | KRBL | KRIMBEL TRUCKING CO | | | SCAC3 |
| 4443 | KRBM | KREBS MOVING & STORAGE INC | | | SCAC3 |
| 4444 | KRBO | KRAFT BROTHERS | | | SCAC3 |
| 4445 | KRBR | K R B TRANSPORT LTD | | | SCAC4 |
| 4446 | KRBS | KRESS, ALAN J | | | SCAC3 |
| 4447 | KRBT | KIRBY TRANSPORT INC | | | SCAC3 |
| 4448 | KRBV | KRYSTAL LOGISTICS USA | | | SCAC4 |
| 4449 | KRBW | KARBOWSKI DISTRIBUTING INC | | | SCAC4 |
| 4450 | KRBY | KIRKEBY, RAYMOND M | | | SCAC3 |
| 4451 | KRC | New Zealand Air Defence Force | Callsign: Kiwi Rescue, | NZ | AVCODES |
| 4452 | KRC | New Zealand Air Defence Force | | | ICAO1 |
| 4453 | KRC | KEEWATIN RAILWAY COMPANY | | | SCAC4 |
| 4454 | KRCA | KETTLE RIVER CANOES | | | SCAC4 |
| 4455 | KRCAL | Krono Chemical S p. z o.o. | | PL | VKM |
| 4456 | KRCC | KEG RIVER CHEMICAL CORP | | | SCAC4 |
| 4457 | KRCF | KINSCHHOFFER TRUCK SERVICE INC | | | SCAC3 |
| 4458 | KRCF | KUSKIE OIL AND REPAIR | | | SCAC4 |
| 4459 | KRCH | KARCHMER, A & SON INC | | | SCAC4 |
| 4460 | KRCHE | Alfa Terminal Szczecin Sp. z o.o. | | PL | VKM |
| 4461 | KRCI | KIAMICHI RAILROAD COMPANY, INC. | | | PWRC |
| 4462 | KRCI | KARSTEN CORPORATION | | | SCAC3 |
| 4463 | KRCK | KRUCKER MANUFACTURING LIMITED | | | SCAC4 |
| 4464 | KRCL | KRC LOGISTICS LLC | | | SCAC4 |
| 4465 | KRCM | K & R COMPANY | | | SCAC4 |
| 4466 | KRCN | K & R CARRIERS INC | | | SCAC4 |
| 4467 | KRCO | KERN ROCK COMPANY | | | SCAC3 |
| 4468 | KRCP | K R C PRODUCTS | | | SCAC3 |
| 4469 | KRCP | KERO CHIPPING LTD | | | SCAC4 |
| 4470 | KRCQ | KRUMROY CARTAGE INC | | | SCAC3 |
| 4471 | KRCS | KNIFE RIVER CORPORATION - SOUTH | | | SCAC4 |
| 4472 | KRCU | KIWIRAIL | | NZ | BIC |
| 4473 | KRCX | R.M. Johnson Co., Inc. | 7/2005 (not listed) | | NAKINA |
| 4474 | KRCX | R.M. Johnson Co. d/b/a Kimball Railcar Services | eliminated 1/2005 | | NAKINA |
| 4475 | KRCX | Merchants Despatch Transportation Corp. (reporting marks for Keefe Packing Co.) | 7/1937-4/1938; 1/1941 (not listed) | | NAKINA |
| 4476 | KRCX | Keefe Packing Co. (Merchants Despatch Transportation Corp.) | Apr-38 | | NRHS |
| 4477 | KRCX | *KEEFE PACKING CO. (MERCHANTS DESPATCH TRANSPORTATION CORP.) | | | PWRC |
| 4478 | KRCX | *KOKOMO RAIL COMPANY, INC. | | | PWRC |
| 4479 | KRCX | +R. M. JOHNSON CO. d/b/a KIMBALL RAILCAR SERVICES | | | PWRC |
| 4480 | KRCX | KIMBALL RAILCAR SERVICES | | | SCAC4 |
| 4481 | KRCZ | KNIFE RIVER COAL COMPANY | | | PWRC |
| 4482 | KRDB | KREY DISTRIBUTING CO | | | SCAC3 |
| 4483 | KRDC | KRISTEN DISTRIBUTING CO | | | SCAC4 |
| 4484 | KRDI | KRAFT DELIVERY & STORAGE SERVICE | | | SCAC3 |
| 4485 | KRDI | KRISDA INC | | | SCAC4 |
| 4486 | KRDN | KRIS-DON INC | | | SCAC3 |
| 4487 | KRDT | KOROLITE ENGINEERED PANEL STRUCTURE | | | SCAC4 |
| 4488 | KRDX | K.R. D-X Co. | added 7/1967; 4/1970-1/1980; eliminated 4/1988 | | NAKINA |
| 4489 | KRDX | K.R. D-X Co. | added 7/67; 4/70-1/80; eliminated 4/88 | | NRHS |
| 4490 | KRDX | K.R. D-X CO. | | | PWRC |
| 4491 | KRDX | KRDX Co. | | | RSRV |
| 4492 | KRE | Aerosucre, S.A. | IATA: 6N, Callsign: Aerosucre, Designator 6N recalled by IATA. Founded in 1969. | CO | AVCODES |
| 4493 | KRE | Aerosucre, S.A. | Callsign: Aerosucre, Designator 6N recalled by IATA. Founded in 1969. | CO | AVCODES |
| 4494 | KRE | AeroSucre | | | ICAO1 |
| 4495 | KREB | KREBS TRUCKING | | | SCAC4 |
| 4496 | KREBS | Krebs Gleisbau | | D | TRAFFIC |
| 4497 | KREBS | Krebs GmbH & Co KG | | DE | VKM |
| 4498 | KREC | KRAFT EXPRESS INC | | | SCAC3 |
| 4499 | KRED | KREIDER TRUCKING INC | | | SCAC3 |
| 4500 | KREE | KRONE, EARL E INC | | | SCAC3 |
