| 1901 | USGU | MILITARY SDDC | | USA | BIC |
| 1902 | USGX | Union Sugar Co. | added 1/1982; eliminated 1/1987 | | NAKINA |
| 1903 | USGX | Union Sugar Division, Holly Sugar Corp. | added 1/1987; added 7/1990 | | NAKINA |
| 1904 | USGX | Holly Sugar Corp. | added 7/1990; 1/1994; eliminated 4/1994 | | NAKINA |
| 1905 | USGX | U.S. Magnesium, LLC | added 10/2008; eliminated 1/2009 | | NAKINA |
| 1906 | USGX | Union Sugar Co. | added 1/82; eliminated 1/87 | | NRHS |
| 1907 | USGX | Union Sugar Division, Holly Sugar Corp. | added 1/87; added 7/90 | | NRHS |
| 1908 | USGX | Holly Sugar Corp. | added 7/90; 1/94; eliminated 4/94 | | NRHS |
| 1909 | USGX | *HOLLY SUGAR CORPORATION [UNION SUGAR COMPANY] | | | PWRC |
| 1910 | USGX | +US MAGNESIUM, LLC | | | PWRC |
| 1911 | USGX | Union Sugar | | | RSRV |
| 1912 | USGX | US MAGNESIUM LLC | | | SCAC4 |
| 1913 | USH | U.S. Helicopter Corporation | IATA: UH, Callsign: US Heli, Founded in 2004. Ceased operations on 25 September 2009. | USA | AVCODES |
| 1914 | USH | US Helicopter | | | ICAO1 |
| 1915 | USHL | UNITED SHIPPING LINES | | | SCAC4 |
| 1916 | USHM | UNITED SHIPMENT INC | | | SCAC4 |
| 1917 | USHO | U S HORSE TRANSPORT | | | SCAC4 |
| 1918 | USHR | USHER TRANSPORT INC | | | SCAC4 |
| 1919 | USHT | UNIVERSAL | | | SCAC4 |
| 1920 | USIC | U.S. INTERMODAL CORP. | | | PWRC |
| 1921 | USIC | U S INTERMODAL CORP OF SOUTH CAROLI | | | SCAC4 |
| 1922 | USIE | U S INTER-MEX TRANSPORTATION INC | | | SCAC4 |
| 1923 | USII | USA TRANSFER INTERNATIONAL INC | | | SCAC4 |
| 1924 | USIL | USA TRUCK INC (LOGISTICS OPERATIONS | | | SCAC4 |
| 1925 | USIM | U S INTERMODAL MARITIME INC | | | SCAC4 |
| 1926 | USIO | US & INTERNATIONAL BOUND MAIL INC | | | SCAC4 |
| 1927 | USIR | USA TRUCK INC (REGIONAL OPERATIONS) | | | SCAC4 |
| 1928 | USIS | UTILICASE SOLUTIONS INC | | | SCAC4 |
| 1929 | USIT | USA TRUCK, INC. | | | SCAC1 |
| 1930 | USIT | USA Truck | | | SCAC2 |
| 1931 | USIT | USA TRUCK INC | | | SCAC4 |
| 1932 | USIU | USA TRUCK INC | | | SCAC4 |
| 1933 | USIV | USA SERVICES INCORPORATED | | | SCAC4 |
| 1934 | USIX | U.S. Industrial Alcohol Co. | 7/1937-4/1938 | | NAKINA |
| 1935 | USIX | U.S. Industrial Chemicals, Inc. | 1/1941-1/1946 | | NAKINA |
| 1936 | USIX | U.S. Industrial Chemicals Co., Division of National Distillers and Chemical Corp. | added 10/1977; 1/1980; eliminated 7/1987 | | NAKINA |
| 1937 | USIX | USI Chemicals Co., Division of National Distillers & Chemical Corp. | added 7/1987; eliminated 7/1988 | | NAKINA |
| 1938 | USIX | Quantum Chemical Corp., USI Division | added 7/1988; 1/1994; eliminated 4/1998 | | NAKINA |
| 1939 | USIX | Equistar Chemicals, LP | added 4/1998; 7/2000-7/2005; eliminated 10/2007 | | NAKINA |
| 1940 | USIX | U.S. Industrial Alcohol Co. | Apr-38 | | NRHS |
| 1941 | USIX | U.S. Industrial Chemicals Co., Division of National Distillers and Chemical Corp. | 1/80; eliminated 7/87 | | NRHS |
| 1942 | USIX | USI Chemicals Co., Division of National Distillers & Chemical Corp. | added 7/87; eliminated 7/88 | | NRHS |
| 1943 | USIX | Quantum Chemical Corp., USI Division | added 7/88; 1/94; eliminated 4/98 | | NRHS |
| 1944 | USIX | Equistar Chemicals, LP | added 4/98; 7/2000 | | NRHS |
| 1945 | USIX | EQUISTAR CHEMICALS LP [QUANTUM CHEMICAL CORPORATION, US INDUSTRIAL CHEMICALS DIV.; US INDUSTRIAL ALCOHOL CO.] | | | PWRC |
| 1946 | USIX | US Industrial Chemicals | | | RSRV |
| 1947 | USIX | EQUISTAR CHEMICALS LP | | | SCAC4 |
| 1948 | USIZ | UNITED STATES SILICA | | | PWRC |
| 1949 | USJ | US Jet, Inc. | Callsign: Usjet, | USA | AVCODES |
| 1950 | USJ | US Jet | | | ICAO1 |
| 1951 | USJA | USA JET AIRLINES INC | | | SCAC4 |
| 1952 | USK | Skif-Air, LLC | Callsign: Skif-Air, | UA | AVCODES |
| 1953 | USK | Skif-Air | | | ICAO1 |
| 1954 | USKC | US TRUCKING LLC | | | SCAC4 |
| 1955 | USKG | US TRUCKING | | | SCAC4 |
| 1956 | USKL | US TRUCK LLC | | | SCAC4 |
| 1957 | USL | U S A LINES INC | | | SCAC4 |
| 1958 | USLC | USA LOGISTICS INC | | | SCAC4 |
| 1959 | USLD | Detroit, Toledo and Ironton R.R. Co. | 4/1970-1/1980; eliminated 1/1980 | | NAKINA |
| 1960 | USLD | Detroit, Toledo and Ironton R.R. Co. | 4/70-1/80; eliminated 1/80 | | NRHS |
| 1961 | USLD | DETROIT, TOLEDO & IRONTON RAILROAD CO. | | | PWRC |
| 1962 | USLE | U S LINKS WORLDWIDE INC | | | SCAC4 |
| 1963 | USLF | St. Louis-San Francisco Ry. Co. | 4/1970-1/1980; eliminated 1/1981 | | NAKINA |
| 1964 | USLF | Burlington Northern Inc. | added 1/1981; eliminated 7/1981 | | NAKINA |
| 1965 | USLF | Burlington Northern R.R. Co. | added 7/1981; eliminated 7/1985 | | NAKINA |
| 1966 | USLF | St. Louis-San Francisco Ry. Co. | 4/70-1/80; eliminated 1/81 | | NRHS |
| 1967 | USLF | Burlington Northern Inc. | added 1/81; eliminated 7/81 | | NRHS |
| 1968 | USLF | Burlington Northern R.R. Co. | added 7/81 | | NRHS |
| 1969 | USLF | BURLINGTON NORTHERN RAILROAD [ST. LOUIS-SAN FRANCISCO RWY. CO.] | | | PWRC |
| 1970 | USLF | St. Louis-San Francisco Railway (BNSF Railway) | | | RSRV |
| 1971 | USLG | U S LOGISTICS INC | | | SCAC4 |
| 1972 | USLI | U S LOGISTICS INC | | | SCAC4 |
| 1973 | USLJ | USLC | | | SCAC4 |
| 1974 | USLN | US LOGISTICS INC | | | SCAC4 |
| 1975 | USLO | USELTON OIL CO INC | | | SCAC4 |
| 1976 | USLP | U S LUMBER GROUP LLC | | | SCAC4 |
| 1977 | USLR | US SERVICES LLC | | | SCAC4 |
| 1978 | USLT | USA LOGISTICS INC | | | SCAC4 |
| 1979 | USLU | UNIVERSAL STAR SHIPPING LINE LLC | | UAE | BIC |
| 1980 | USLU | UNITED STATES LINES, INC. | | | PWRC |
| 1981 | USLU | United States Lines | | | RSRV |
| 1982 | USLU | UNITED STATES LINES, INC. | | | SCAC4 |
| 1983 | USLX | United States Railway Equipment Co. | eliminated 10/1967 | | NAKINA |
| 1984 | USLX | United States Railway Leasing Co. | added 10/1967; 4/1970; eliminated 1/1973 | | NAKINA |
| 1985 | USLX | United States Railway Equipment Co. | added 1/1973; 1/1975; eliminated 7/1979 | | NAKINA |
| 1986 | USLX | United States Leasing Co. | added 7/1979 | | NAKINA |
| 1987 | USLX | United States Railway Leasing Co. | 1/1980; eliminated 10/1980 | | NAKINA |
| 1988 | USLX | Evans Railcar Leasing Co. | added 10/1980; eliminated 4/1988 | | NAKINA |
| 1989 | USLX | Itel Rail Corp. | added 4/1988; eliminated 10/1992 | | NAKINA |
| 1990 | USLX | General Electric Railcar Services Corp. | added 10/1992; 1/1994; eliminated 1/2000 | | NAKINA |
| 1991 | USLX | General Electric Rail Services Corp. | added 1/2000; 7/2000-7/2005 | | NAKINA |
| 1992 | USLX | United States Railway Equipment Co. | eliminated 10/67 | | NRHS |
| 1993 | USLX | United States Railway Leasing Co. | added 10/67; 4/70; eliminated 1/73 | | NRHS |
| 1994 | USLX | United States Railway Equipment Co. | added 1/73; 1/75; eliminated 7/79 | | NRHS |
| 1995 | USLX | United States Leasing Co. | added 7/79 | | NRHS |
| 1996 | USLX | United States Railway Leasing Co. | 1/80; eliminated 10/80 | | NRHS |
| 1997 | USLX | Evans Railcar Leasing Co. | added 10/80; eliminated 4/88 | | NRHS |
| 1998 | USLX | Itel Rail Corp. | added 4/88; eliminated 10/92 | | NRHS |
| 1999 | USLX | General Electric Railcar Services Corp. | added 10/92; 1/94; eliminated 1/2000 | | NRHS |
| 2000 | USLX | General Electric Rail Services Corp. | added 1/2000; 7/2000 | | NRHS |
