| 1801 | KFLL | KIRK FREIGHT LINE LTD | | | SCAC3 |
| 1802 | KFLN | KINGMAN DEDICATED SERVICE INC | | | SCAC4 |
| 1803 | KFLO | KF LOGISTICS INC | | | SCAC4 |
| 1804 | KFML | KOLA FEED MILL LTD | | | SCAC4 |
| 1805 | KFMS | KAPALUA FUEL & MARINE SERVICES INC | | | SCAC4 |
| 1806 | KFMT | KFM TRANSPORT | | | SCAC4 |
| 1807 | KFMX | Oils Unlimited | 1/1975-1/1994; 7/2000-7/2005 (not listed) | | NAKINA |
| 1808 | KFMX | The Kansas Flour Mills Co. | 7/1923 | | NAKINA |
| 1809 | KFMX | Oils Unlimited | 1/75-7/2000 | | NRHS |
| 1810 | KFMX | *KANSAS FLOUR MILLS CO. | | | PWRC |
| 1811 | KFMX | +OILS UNLIMITED | | | PWRC |
| 1812 | KFMX | Kansas Flour Mills (Oils Unlimited) | | | RSRV |
| 1813 | KFNA | KONTROLLER FREIGHT NETWORK INC | | | SCAC4 |
| 1814 | KFNB | Kaiserliche Franz-Josef NordBahn | | A | TRAFFIC |
| 1815 | KFND | KOFFORD, NED TRUCKING INC | | | SCAC3 |
| 1816 | KFNL | KELVIN FORTUNE LTD GLASGOW UK | | | SCAC3 |
| 1817 | KFOC | KONOWAL FUEL OIL CO LLC | | | SCAC4 |
| 1818 | KFOO | KNOTTS FOODS | | | SCAC4 |
| 1819 | KFOR | | | X | TRAFFIC |
| 1820 | KFPE | KRAFT FOODS GLOBAL INC (PRIVATE FLE | | | SCAC4 |
| 1821 | KFPM | KRAFT FOODS GLOBAL INC (PRIVATE FLE | | | SCAC4 |
| 1822 | KFPX | Koppers Co., Inc. | added 10/1969; 4/1970-1/1980; eliminated 10/1987 | | NAKINA |
| 1823 | KFPX | Koppers Co., Inc. | added 10/69; 4/70-1/80; eliminated 10/87 | | NRHS |
| 1824 | KFPX | KOPPERS CO. | | | PWRC |
| 1825 | KFPX | Koppers | | | RSRV |
| 1826 | KFR | Kingfisher Airlines Limited | IATA: IT, Callsign: Kingfisher, AOC temporarily suspended by Indian DGAC due financial issues. | IND | AVCODES |
| 1827 | KFR | Kingfisher Airlines | IATA: IT | | ICAO1 |
| 1828 | KFR | Kettle Falls International Ry. LLC | 7/2005 | | NAKINA |
| 1829 | KFR | KETTLE FALLS INTERNATIONAL RWY. LLC | | | PWRC |
| 1830 | KFR | Kettle Falls International Railway | | | RSRV |
| 1831 | KFR | KETTLE FALLS INTERNATIONAL RAILWAY | | | SCAC4 |
| 1832 | KFRC | KAT FUEL RESOURCES | | | SCAC4 |
| 1833 | KFRD | KENNEDY, FRED TRUCKING INC | | | SCAC3 |
| 1834 | KFRD | KENNEDY, FRED TRUCKING INC | | | SCAC4 |
| 1835 | KFRG | KSI FREIGHT | | | SCAC4 |
| 1836 | KFRH | KERFORD, ROBERT H | | | SCAC3 |
| 1837 | KFRL | KLONDIKE FARMS LTD | | | SCAC4 |
| 1838 | KFRS | KEFOR STRUCTURES LTEE | | | SCAC4 |
| 1839 | KFRU | KILFROST LIMITED | | | SCAC4 |
| 1840 | KFRX | Chicago Freight Car Leasing Co. | added 1/1970; 4/1970-1/1975; eliminated 1/1983 | | NAKINA |
| 1841 | KFRX | Chicago Freight Car Leasing Co. | added 1/70; 4/70-1/75; eliminated 1/83 | | NRHS |
| 1842 | KFRX | CHICAGO FREIGHT CAR LEASING CO. | | | PWRC |
| 1843 | KFS | Kalitta Flying Service, Inc. | Callsign: Kalitta, | USA | AVCODES |
| 1844 | KFS | Kalitta Charters LLC | IATA: K9, Callsign: Kalitta, | USA | AVCODES |
| 1845 | KFS | Kalitta Charters | | | ICAO1 |
| 1846 | KFS | Kansai freight service | | J | TRAFFIC |
| 1847 | KFSA | KFS INC | | | SCAC4 |
| 1848 | KFSB | KTL FREIGHT SYSTEMS INC | | | SCAC4 |
| 1849 | KFSC | KENS FEED STORE INC | | | SCAC4 |
| 1850 | KFSI | KING FREIGHT SYSTEMS INC | | | SCAC3 |
| 1851 | KFSI | KLUTCH FREIGHT SOLUTIONS INC | | | SCAC4 |
| 1852 | KFSN | KFS INC | | | SCAC4 |
| 1853 | KFSP | KUFA SPORTS ENTERPRISE LTD | | | SCAC4 |
| 1854 | KFSX | Kurtz Farm Service | 4/1938 (not listed) | | NAKINA |
| 1855 | KFSX | KURTZ FARM SERVICE | | | PWRC |
| 1856 | KFT | Air Kraft Mir | | | ICAO1 |
| 1857 | KFTA | KING FRESH TRANSPORTATION | | | SCAC4 |
| 1858 | KFTK | KING FARMS TRUCKING LLC | | | SCAC4 |
| 1859 | KFTN | K & F TRANSPORTATION INC | | | SCAC3 |
| 1860 | KFTP | KOPPERS FISHING & TACKLE CORP | | | SCAC4 |
| 1861 | KFTQ | K F TRUCKING | | | SCAC4 |
| 1862 | KFTU | KAERCHER FUTURETECH GMBH | | D | BIC |
| 1863 | KFTX | J & J Railcar Leasing, LLC | 7/2005 (not listed); added 1/2008 | | NAKINA |
| 1864 | KFTX | J & J RAILCAR LEASING, LLC. | | | PWRC |
| 1865 | KFTX | J and J Railcar Leasing | | | RSRV |
| 1866 | KFTX | J & J RAILCAR LEASING LLC | | | SCAC4 |
| 1867 | KFUE | KEEHAN FUELS | | | SCAC4 |
| 1868 | KFUI | KING FREIGHT (USA) INC | | | SCAC4 |
| 1869 | KFUN | KERRY FREIGHT (USA) INC | | | SCAC4 |
| 1870 | KFV | Központi Felépítményvizsgáló Kft. | | HU | VKM |
| 1871 | KFWP | KAUFFMAN, W P INC | | | SCAC3 |
| 1872 | KG | Linea Aerea I.A.A.C.A. (L.A.I.) | ICAO: BNX, Callsign: Air Barinas, IATA Prefix: 102, Founded in 1992. Ceased operations on 27 September 2006. | YV | AVCODES |
| 1873 | KG | Key Lime Air Corporation | ICAO: LYM, Callsign: Key Lime, IATA designator changed to KG. | USA | AVCODES |
| 1874 | KG | Air Sur | ICAO: NCR, Callsign: Nacar, Formerly Canafrica Transportes A�reos SA | E | AVCODES |
| 1875 | KG | Caledonian Airways Limited | ICAO: CKT, Callsign: Caledonian, Merged into JMC 27 March 2002. | GB | AVCODES |
| 1876 | KG | Canafrica Transportes Aéreos SA | ICAO: NCR, Callsign: Nacar, Renamed Air Sur | E | AVCODES |
| 1877 | KG | Orion Airways | ICAO: ORN, Callsign: Orion, Founded in 1979. Merged into Britannia Airways. | GB | AVCODES |
| 1878 | KG | Cardinal Air Taxis Ltd. | Callsign: Cardinal, | GB | AVCODES |
| 1879 | KG | Empresa de Aviacion Aerogaviota, S.A. | ICAO: GTV, Callsign: Gaviota, Founded on 02 December 1982. | C | AVCODES |
| 1880 | KG | Key Lime Air Corporation | ICAO: LYM, Callsign: Key Lime, IATA designator changed from KG*. | USA | AVCODES |
| 1881 | KG | Kölngleis Gleisbau GmbH & Co. KG | | DE | VKM |
| 1882 | KGA | Kyrgyzstan Airlines / National Airline | IATA: R8, Callsign: Kyrgyz, IATA Prefix: 758, Founded in 1993. Ceased operations in 2005. | KS | AVCODES |
| 1883 | KGA | Kyrghyzstan Airlines | IATA: K2, Callsign: Kyrair, IATA Prefix: 758, ICAO designator changed to KGY | KS | AVCODES |
| 1884 | KGA | Kyrgyzstan Airlines | IATA: R8 | | ICAO1 |
| 1885 | KGA | Karlskoga Kommun | | SE | VKM |
| 1886 | KGAC | KGA CARRIERS INC | | | SCAC4 |
| 1887 | KGAJ | KNAGGS, ARNOLD JAMES | | | SCAC4 |
| 1888 | KGAQ | KING, GARFIELD A | | | SCAC3 |
| 1889 | KGAT | KUESEL, G A TRUCKING | | | SCAC3 |
| 1890 | KGB | Kyrgyz General Aviation | Callsign: Kemin, | KS | AVCODES |
| 1891 | KGB | Sapsan Airlines d/b/a SAPSAN Airline | IATA: S2, Callsign: Sapsan, IATA Prefix: 708, | KS | AVCODES |
| 1892 | KGB | Kyrgz General Aviation | | | ICAO1 |
| 1893 | KGB | Kewaunee, Green Bay & Western R.R. Co. | 4/1938-10/1966 | | NAKINA |
| 1894 | KGB | Kewaunee, Green Bay & Western R.R. Co. | 4/38-10/66 | | NRHS |
| 1895 | KGB | FOX VALLEY & WESTERN, LTD. [KEWAUNEE, GREEN BAY & WESTERN RR] | | | PWRC |
| 1896 | KGB | Kewaunee, Green Bay & Western R.R. Co. | | USA | TRAFFIC |
| 1897 | KGBG | KINGSBURG TRUCKING INC | | | SCAC3 |
| 1898 | KGBL | KGB TRUCKING LLC | | | SCAC4 |
| 1899 | KGBQ | K G B DISTRIBUTORS INC | | | SCAC3 |
| 1900 | KGBTK | Köhnke Geräte- und Bau GmbH | | DE | VKM |
