| 1 | OZ | Asiana Airlines, Inc. | ICAO: AAR, Callsign: Asiana, IATA Prefix: 988, | ROK | AVCODES |
| 2 | OZ | Ozark Airlines | ICAO: OZA, Callsign: Ozark, Ceased operations | USA | AVCODES |
| 3 | OZ | OLDSMOBILE | | | PWRC |
| 4 | OZA | Ozark Airlines | IATA: OZ, Callsign: Ozark, Ceased operations | USA | AVCODES |
| 5 | OZAF | OZARK TIMBER FREIGHT INC | | | SCAC4 |
| 6 | OZAK | OZARK ATLANTIC TRANSPORTATION LLC | | | SCAC4 |
| 7 | OZAN | ORZAN TRANSPORTATION CORP | | | SCAC3 |
| 8 | OZAN | ONE ZERO NING EIGHT ONE ZERO EIGHT | | | SCAC4 |
| 9 | OZAR | OZARK TRANSFER, INC | | | SCAC3 |
| 10 | OZAT | OZARK TRANSPORTATION INC | | | SCAC3 |
| 11 | OZAT | ONE ZERO TRANSPORT LLC | | | SCAC4 |
| 12 | OZB | Zona Blava, S.L. | Callsign: Zona Blava, | E | AVCODES |
| 13 | OZCH | OZARK CHARTERS INC | | | SCAC3 |
| 14 | OZCH | OZEE TRUCKING | | | SCAC4 |
| 15 | OZCL | OPTIMIZE COURIER L L C | | | SCAC4 |
| 16 | OZCO | OZARK CARTAGE CO INC | | | SCAC3 |
| 17 | OZCX | Ozark-Mahoning Co. | 1/1950-4/1970; eliminated 7/1972 | | NAKINA |
| 18 | OZCX | Ozark Chemical Co. | 7/1937-1/1941 (not listed); 1/1943-4/1947 | | NAKINA |
| 19 | OZCX | Ozark-Mahoning Co. | 1/52-4/70 | | NRHS |
| 20 | OZCX | OZARK CAR CORP. [OZARK-MAHONING CO.; OZARK CHEMICAL CO.] | | | PWRC |
| 21 | OZCX | OZARK-MAHONING CO | | | SCAC3 |
| 22 | OZEE | OZEE, W T | | | SCAC3 |
| 23 | OZEE | OZE ROD SHOP INC | | | SCAC4 |
| 24 | OZEK | OZE TRUCKING INC | | | SCAC3 |
| 25 | OZEK | ONE ZERO SIX ZERO SIX SEVEN ZERO (1 | | | SCAC4 |
| 26 | OZEKI | Ozeki Kanko Bus Co. | | J | TRAFFIC |
| 27 | OZET | ONE ZERO EIGHT THREE THREE ONE TWO | | | SCAC4 |
| 28 | OZEY | ONE ZERO EIGHT ONE EIGHT (10818) YU | | | SCAC4 |
| 29 | OZFF | ONE ZERO FOUR FOUR NINE FIVE (10449 | | | SCAC4 |
| 30 | OZG | Zori Air Cargo | Callsign: Zori Cargo, Ceased Operations. | BG | AVCODES |
| 31 | OZHS | ORTIZ, HECTOR S | | | SCAC4 |
| 32 | OZIE | OZIER, BARNEY TRUCKING | | | SCAC3 |
| 33 | OZJ | OzJet Airlines Pty Limited | IATA: O7, Callsign: Ausjet, | AUS | AVCODES |
| 34 | OZJ | Ozjet Airlines | IATA: O7 | | ICAO1 |
| 35 | OZKF | OZARK FORWARDING CO | | | SCAC3 |
| 36 | OZKF | OZARK FORWARDING INC | | | SCAC4 |
| 37 | OZKM | OZARK TRANSMODAL | | | SCAC4 |
| 38 | OZKV | OZARK VAN LINES INC | | | SCAC4 |
| 39 | OZKX | Union Tank Car Co. | added 7/1962; 7/1965-4/1970; eliminated 7/1973 | | NAKINA |
| 40 | OZKX | Ozark Tank Car Co. | 1/1952-4/1961; eliminated 7/1962 | | NAKINA |
| 41 | OZKX | Deep Rock Oil Corp. | 7/1937-1/1950 | | NAKINA |
| 42 | OZKX | Ozark Car Corp. | 7/1932 | | NAKINA |
| 43 | OZKX | Ozark Car Corp. (Deep Rock Oil Corp.) | 7/1935 | | NAKINA |
| 44 | OZKX | Ozark Car Corp. (Deep Rock Oil Corp.) | Apr-38 | | NRHS |
| 45 | OZKX | Ozark Tank Car Co. | 1/52-4/61 | | NRHS |
| 46 | OZKX | Union Tank Car Co. | 7/65-4/70; eliminated 7/73 | | NRHS |
| 47 | OZKX | UNION TANK CAR CO. [OZARK TANK CAR CO.; DEEP ROCK OIL CORP.; OZARK CAR CO.] | | | PWRC |
| 48 | OZML | OZMILLION SHIPPING CORP. | | | SCAC3 |
| 49 | OZMU | GJSC OTEW | | BY | BIC |
| 50 | OZMV | OZ MOVERS | | | SCAC3 |
| 51 | OZNO | ONE ZERO NINE ONE FIVE NINE TWO (10 | | | SCAC4 |
| 52 | OZNT | ONE ZERO NINE THREE EIGHT FIVE FOUR | | | SCAC4 |
| 53 | OZNW | ONE ZERO NINE SIX SIX FOUR SIX (109 | | | SCAC4 |
| 54 | OZOF | ONE ZERO ONE ONE SIX ONE SEVEN ONE | | | SCAC4 |
| 55 | OZOI | ONE ZERO ONE (101) INNOVATIONS LLC | | | SCAC4 |
| 56 | OZON | OZONE MOTOR LINE INC | | | SCAC3 |
| 57 | OZOT | ONE ZERO ONE (101) TRANSPORT INC | | | SCAC4 |
| 58 | OZR | Ozark Air Lines, Inc. | IATA: ZO, Name changed to Ozark Air Lines, Inc. d/b/a Great Plains Airlines. ICAO designator changed to GRP | USA | AVCODES |
| 59 | OZR | Ozark Air Lines | IATA: OZ | | ICAO1 |
| 60 | OZRK | OZARK MOTOR LINES | | | SCAC3 |
| 61 | OZRK | OZARK MOTOR LINES | | | SCAC4 |
| 62 | OZRT | OZARK TRUCKING INC | | | SCAC3 |
| 63 | OZRT | OZARK TRUCKING INC | | | SCAC4 |
| 64 | OZRU | ÖZER ELEKTRIK SAN. VE TIC. LDT. ŞTI. | | TR | BIC |
| 65 | OZSL | OZEAN/STENNES LINIEN | | | PWRC |
| 66 | OZSM | OZARK SEAFOOD & MEATS INC | | | SCAC3 |
| 67 | OZSS | ONE ZERO SIX SEVEN TWO SEVEN THREE | | | SCAC4 |
| 68 | OZT | Premier Flight Center, LLC | Callsign: Ozark Tech, | USA | AVCODES |
| 69 | OZTB | OZARK TRUCK BROKERS INC | | | SCAC3 |
| 70 | OZTC | OZAR TRANSPORTATION INC | | | SCAC4 |
| 71 | OZTL | OZ TRANSTANK LIMITED | | | SCAC3 |
| 72 | OZTL | OZ TRUCKING LTD | | | SCAC4 |
| 73 | OZTN | ONE ZERO THREE NINE ZERO ONE TWO (1 | | | SCAC4 |
| 74 | OZTR | OZARK TRANSFER & STORAGE | | | SCAC3 |
| 75 | OZTR | OZAETA TRANSPORTES | | | SCAC4 |
| 76 | OZTS | OZINGA TRANSPORTATION SYSTEMS, INC | | | SCAC3 |
| 77 | OZTS | OZINGA TRANSPORTATION SYSTEMS INC | | | SCAC4 |
| 78 | OZTT | ONE ZERO TWO TWO EIGHT ZERO FOUR (1 | | | SCAC4 |
| 79 | OZTU | OZTURK NAKLIYAT VE INSAAT SAN.TIC.LTD.STI | | TR | BIC |
| 80 | OZTU | OZTURK NAKLIYAT VE INSAAT SAN TIC L | | | SCAC4 |
| 81 | OZU | Khozu-Avia Aircompany | Callsign: Hozavi, | KZ | AVCODES |
| 82 | OZU | Hozu-Avia | | | ICAO1 |
| 83 | OZW | SkyWest Airlines Pty. Ltd. | IATA: XR, Callsign: Ozwest, IATA Prefix: 608, Name changed to Virgin Australia Regional Airlines Pty Ltd. Designator XR reinstated by IATA | AUS | AVCODES |
| 84 | OZW | Virgin Australia Regional Airlines Pty Ltd. | IATA: XR, Callsign: Ozwest, IATA Prefix: 608, Designator XR recalled by IATA. Name changed from SkyWest Airlines Pty. Ltd. Designator XR reinstated by IATA | AUS | AVCODES |
| 85 | OZW | Virgin Australia Regional Airlines Pty Ltd. | Callsign: Ozwest, IATA Prefix: 608, Designator XR recalled by IATA. Name changed from SkyWest Airlines Pty. Ltd. Designator XR reinstated by IATA | AUS | AVCODES |
| 86 | OZW | Skywest Airlines | | | ICAO1 |
| 87 | OZX | Ozone Co., Inc. | 7/1937-10/1966; eliminated 1/1967 | | NAKINA |
| 88 | OZX | Ozone Co., Inc. | 4/38-10/66; eliminated 1/67 | | NRHS |
| 89 | OZX | OZONE CO., INC. | | | PWRC |
| 90 | OZXQ | OZARK EXPRESS | | | SCAC3 |
| 91 | OZZQ | OZZELLO CONSTRUCTION CO | | | SCAC3 |
| 92 | OZZQ | ONE SEVEN ZERO ZERO SIX ZERO FOUR ( | | | SCAC4 |
