| 1901 | OLOT | OSCARS LOGISTICS | | | SCAC4 |
| 1902 | OLOV | OLSON, OLIVER J & CO | | | SCAC3 |
| 1903 | OLPC | OLYMPIC MOVING & STORAGE | | | SCAC4 |
| 1904 | OLPD | OLYMPIC DELIVERY SERVICE INC | | | SCAC3 |
| 1905 | OLPE | OILTON PETROLEUM INC | | | SCAC3 |
| 1906 | OLPI | OLYMPIC TRANSFER & STORAGE INC | | | SCAC3 |
| 1907 | OLPP | OPERATOR LOGISTYCZNY PALIW PŁYNNYCH Sp. z o.o. | | PL | VKM |
| 1908 | OLPQ | OLYMPIC TRANSPORTATION CO | | | SCAC3 |
| 1909 | OLPT | OLPIN TRUCKING | | | SCAC3 |
| 1910 | OLPW | OLYMPIA TANKER CORPORATION | | | SCAC3 |
| 1911 | OLPW | OLYMPIA TANKER CORPORATION | | | SCAC4 |
| 1912 | OLR | Colaereos | Callsign: Colaereos, | EC | AVCODES |
| 1913 | OLR | Colaereos | | | ICAO1 |
| 1914 | OLRC | OLEARY CONSTRUCTION CO | | | SCAC3 |
| 1915 | OLRS | OLEARS INC | | | SCAC4 |
| 1916 | OLRT | OLD RELIABLE TRANSPORTATION INC | | | SCAC3 |
| 1917 | OLS | SOL S.A. Lineas Aereas | IATA: 8R, Callsign: Flight SOL, IATA Prefix: 300, | RA | AVCODES |
| 1918 | OLSB | OLSON, B P | | | SCAC3 |
| 1919 | OLSC | OLD STYLE CARTAGE | | | SCAC3 |
| 1920 | OLSC | OINOUSSIAN LADY SPECIAL MARITIME EN | | | SCAC4 |
| 1921 | OLSD | OLSON FREIGHT EXPRESS LTD. | | | SCAC3 |
| 1922 | OLSD | OLSEN TRANSPORT INC | | | SCAC4 |
| 1923 | OLSF | OLSEN, FRED CRUISES | | | SCAC4 |
| 1924 | OLSG | OLSON, GARY, TRUCKING, INC | | | SCAC3 |
| 1925 | OLSH | OPTIMAL LOGISTICS SOLUTIONS | | | SCAC4 |
| 1926 | OLSI | OLSON GLASS CO INC | | | SCAC3 |
| 1927 | OLSI | OLYMPIC LOGISTICS SERVICES INC | | | SCAC4 |
| 1928 | OLSJ | OLSON, JOEL | | | SCAC3 |
| 1929 | OLSJ | OLSON, JOEL TRUCKING INC | | | SCAC4 |
| 1930 | OLSK | OPTIMAL LOGISTICS SOLUTIONS LLC | | | SCAC4 |
| 1931 | OLSM | OLSON & SON MOVERS | | | SCAC3 |
| 1932 | OLSM | OCEAN LONGEVITY SHIPPING & | | | SCAC4 |
| 1933 | OLSO | OLSON, AA MOVERS INC | | | SCAC3 |
| 1934 | OLSO | OLSON TRUCKING DIRECT INC | | | SCAC4 |
| 1935 | OLSP | OLSEN TRUCKING | | | SCAC3 |
| 1936 | OLSP | OINOUSSIAN LION SPECIAL MARITIME EN | | | SCAC4 |
| 1937 | OLSQ | OLSON DRAY LINE | | | SCAC3 |
| 1938 | OLSR | OLSON TRUCKING | | | SCAC3 |
| 1939 | OLSS | OLYMPIC STEAMSHIP CO. | | | PWRC |
| 1940 | OLSS | OLYMPIC STEAMSHIP COMPANY | | | SCAC3 |
| 1941 | OLSS | ORCA LOGISTICS INCORPORATED | | | SCAC4 |
| 1942 | OLST | OLSON TRUCK LINE | | | SCAC3 |
| 1943 | OLST | OESTER LOGISTICS | | | SCAC4 |
| 1944 | OLSU | LLC OPTIMAL LOGISTIC | | RUS | BIC |
| 1945 | OLSV | ON-LINE SERVICE CO INC | | | SCAC3 |
| 1946 | OLSW | OY LANGH SHIP AB | | | SCAC4 |
| 1947 | OLSX | ADM TRANSPORTATION COMPANY | | | SCAC4 |
| 1948 | OLT | OLT-Ostfriesische Lufttransport | IATA: OL, Callsign: Oltra, IATA Prefix: 704, Name changed to OLT Express Germany GmbH. | D | AVCODES |
| 1949 | OLT | OLT Express Germany GmbH | IATA: OL, Callsign: Oltra, IATA Prefix: 704, Ceased operations on 27 January 2013 at 12:00pm. Name changed from OLT-Ostfriesische Lufttransport. | D | AVCODES |
| 1950 | OLT | Ostfriesische Lufttransport | IATA: OL | | ICAO1 |
| 1951 | OLT | OLTCHIM SA | | RO | VKM |
| 1952 | OLTA | OCEANLINK/TOPAIR INTERNATIONAL CO L | | | SCAC4 |
| 1953 | OLTB | OLSON TUG BOAT CO | | | SCAC3 |
| 1954 | OLTC | OLIVER LUMBER COMPANY OF TORONTO LI | | | SCAC4 |
| 1955 | OLTD | OPTIM LTD | | | SCAC4 |
| 1956 | OLTE | OLSON, TED ENTERPRISES INC | | | SCAC3 |
| 1957 | OLTE | ONLINE LOGISTICS TRANSPORT LLC | | | SCAC4 |
| 1958 | OLTF | OLYMPIC TRANSFER CORP | | | SCAC4 |
| 1959 | OLTG | OLIVER TRUCKING CORP | | | SCAC3 |
| 1960 | OLTH | OLTHOFF INC | | | SCAC3 |
| 1961 | OLTI | OLSON TRANSFER & STG INC | | | SCAC3 |
| 1962 | OLTI | OLSON TRANSFER & STG INC | | | SCAC4 |
| 1963 | OLTK | OLSEN TRUCKING | | | SCAC3 |
| 1964 | OLTK | OLIVER TRUCKING | | | SCAC4 |
| 1965 | OLTM | OLYMPIC TRAILER MOVERS | | | SCAC3 |
| 1966 | OLTM | OLTMANN, D REEDEREI GMBH & CO KG | | | SCAC4 |
| 1967 | OLTN | OLIVAS TRUCKING | | | SCAC3 |
| 1968 | OLTN | OUILLETTE TRUCKING | | | SCAC4 |
| 1969 | OLTO | OVERLAND TRANSPORT INC | | | SCAC3 |
| 1970 | OLTP | OLSON TRANSPORTATION COMPANY INC | | | SCAC3 |
| 1971 | OLTP | OLIVER TRANSPORT & LEASING INC | | | SCAC4 |
| 1972 | OLTQ | OIL TRANSPORT INC | | | SCAC3 |
| 1973 | OLTR | ONLINE TRUCKING INC | | | SCAC4 |
| 1974 | OLTS | OLINGER TRUCK SERVICE | | | SCAC3 |
| 1975 | OLTS | ONLINE TRANSPORT SYSTEM INC | | | SCAC4 |
| 1976 | OLTU | ODYSSEY FOODTRANS | | USA | BIC |
| 1977 | OLTU | OCEANS LEASING & LOGISTICS LTD | | | SCAC3 |
| 1978 | OLTV | O L TRUCKING | | | SCAC3 |
| 1979 | OLTW | OLYMPIA TOWING CO | | | SCAC3 |
| 1980 | OLTX | Overland Tank Car Co. | 4/1947 | | NAKINA |
| 1981 | OLTX | OVERLAND TANK CAR CO. | | | PWRC |
| 1982 | OLUI | OM LOG USA INC | | | SCAC4 |
| 1983 | OLUM | OLUMAR CORP. | | | SCAC3 |
| 1984 | OLUM | OLUMAR CORP. | | | SCAC4 |
| 1985 | OLUS | OCEANIC LINK USA LLC | | | SCAC4 |
| 1986 | OLV | Aerolineas Olve, S.A. de C.V. | Callsign: Olve, | MEX | AVCODES |
| 1987 | OLV | GA Flight of DE, Inc. d/b/a Airstar | Callsign: Olivia, | USA | AVCODES |
| 1988 | OLV | Aerolineas Olve | | | ICAO1 |
| 1989 | OLVB | OLIVERS BOILER REPAIRS | | | SCAC4 |
| 1990 | OLVC | OLIVIERI, CHARLES R TRANSPORTATION | | | SCAC3 |
| 1991 | OLVD | OLAVE TRANSPORT | | | SCAC4 |
| 1992 | OLVE | OLIVEIRA TRUCKING COMPANY, INCORPOR | | | SCAC3 |
| 1993 | OLVG | OLIVEGROVE SHIPPING COMPANY LTD. | | | SCAC3 |
| 1994 | OLVG | OLIVARES TRUCKING | | | SCAC4 |
| 1995 | OLVJ | OLIVER, JOHN F INC | | | SCAC3 |
| 1996 | OLVN | OLIVE NAVIGATION LTD. | | | SCAC3 |
| 1997 | OLVO | ONLINE FREIGHT SERVICES INC (DOD) | | | SCAC4 |
| 1998 | OLVR | OLIVER TRANSPORTATION INC | | | SCAC3 |
| 1999 | OLVT | OLIVER TRUCKING COMPANY, INC | | | SCAC3 |
| 2000 | OLVW | OLIVE, EDWARD H TRUCKING | | | SCAC3 |
