| 1101 | OFPX | The Otoe Food Products Co. | 7/1932-7/1935 | | NAKINA |
| 1102 | OFPX | OTOE FOOD PRODUCTS CO. | | | PWRC |
| 1103 | OFRM | OELKE FARMS INC | | | SCAC4 |
| 1104 | OFRO | ONE FOUR FIVE SEVEN ZERO THREE ZERO | | | SCAC4 |
| 1105 | OFRS | ORION FREIGHT SERVICES INC | | | SCAC4 |
| 1106 | OFRT | OCEAN FREIGHT TRUCKING INC | | | SCAC4 |
| 1107 | OFS | Fly Me (Pty) Ltd | | ZA | AVCODES |
| 1108 | OFSA | ONE FOUR SEVE FOUR ZERO ONE ONE (14 | | | SCAC4 |
| 1109 | OFSB | OBJECTIVE FINANCE S A | | | SCAC4 |
| 1110 | OFSC | OLD FORGE SERVICES CO | | | SCAC4 |
| 1111 | OFSF | ONE FIVE SIX FIVE ZERO ONE (156501) | | | SCAC3 |
| 1112 | OFSH | OCEAN FAITH SHIPPING S.A. | | | SCAC3 |
| 1113 | OFSH | ONE FIVE SEVEN THREE SIX ZERO ONE ( | | | SCAC4 |
| 1114 | OFSI | OF SERVICE TRANSPORTATION | | | SCAC3 |
| 1115 | OFSI | OCEAN FORTUNE SHIPPING INC | | | SCAC4 |
| 1116 | OFSK | OUTSOURCE FLEET SERVICES INC | | | SCAC4 |
| 1117 | OFSL | ONE FIVE SEVEN ONE ZERO SEVEN FOUR | | | SCAC4 |
| 1118 | OFSM | OT FREIGHT SERVICES | | | SCAC4 |
| 1119 | OFSN | ONE FIVE SEVEN ZERO EIGHT FIVE TWO | | | SCAC4 |
| 1120 | OFSP | OHIO FREIGHT SPECIALISTS INC | | | SCAC3 |
| 1121 | OFST | ORION FOOD SYSTEMS LLC | | | SCAC4 |
| 1122 | OFSU | OILFIELD HIRE AND SERVICES | | GB | BIC |
| 1123 | OFSU | OVERSEAS ENGINEERING & FINANCIAL | | | SCAC3 |
| 1124 | OFSU | OILFIELD HIRE AND SERVICES | | | SCAC4 |
| 1125 | OFSV | ONTARIO FREIGHT SERVICE | | | SCAC4 |
| 1126 | OFSW | ONE FIVE SEVEN SIX TWO FIVE FOUR (1 | | | SCAC4 |
| 1127 | OFSX | Envirosolutions, Inc. | added 7/2007 | | NAKINA |
| 1128 | OFSX | Tucson Electric Power Co. | added 1/1995; 7/2000; eliminated 7/2002; 7/2005 (not listed) | | NAKINA |
| 1129 | OFSX | Ogden Financial Services Corp. | added 7/1985; 1/1994; eliminated 1/1995 | | NAKINA |
| 1130 | OFSX | Ogden Financial Services Corp. | 1/94; eliminated 1/95 | | NRHS |
| 1131 | OFSX | Tucson Electric Power Co. | added 1/95; 7/2000 | | NRHS |
| 1132 | OFSX | *OGDEN FINANCIAL SERVICES CORP. | | | PWRC |
| 1133 | OFSX | *TUCSON ELECTRIC POWER COMPANY | | | PWRC |
| 1134 | OFSX | +ENVIROSOLUTIONS, INC. | | | PWRC |
| 1135 | OFSX | Tucson Electric Power | | | RSRV |
| 1136 | OFSX | TUCSON ELECTRIC POWER COMPANY | | | SCAC4 |
| 1137 | OFSY | OF SHIPPING | | | SCAC4 |
| 1138 | OFTA | OILFIELD TRUCKING SOLUTIONS LLC | | | SCAC4 |
| 1139 | OFTC | OCEAN FRESH TRUCKING CO INC | | | SCAC3 |
| 1140 | OFTE | ONE FIVE THREE EIGHT NINE ONE (1538 | | | SCAC4 |
| 1141 | OFTG | OMEGA FLEET SERVICE INC | | | SCAC4 |
| 1142 | OFTI | OKLAHOMA FUEL TRANSIT LLC | | | SCAC4 |
| 1143 | OFTK | OFFUTT TRUCKING | | | SCAC4 |
| 1144 | OFTM | ONE FOUR TWO FIVE FOUR SEVEN THREE | | | SCAC4 |
| 1145 | OFTN | ONTARIO FIRE TRUCK INC | | | SCAC4 |
| 1146 | OFTO | ONE FIVE THREE ONE T | | | SCAC4 |
| 1147 | OFTP | OFF TRANSPORT INC | | | SCAC3 |
| 1148 | OFTQ | ONE FOUR THREE ZERO TWO ZERO ONE (1 | | | SCAC4 |
| 1149 | OFTS | ONE FOUR TWO SIX SIX FIVE THREE (14 | | | SCAC4 |
| 1150 | OFTT | ONE FIVE FOUR TWO THREE ZERO ZERO ( | | | SCAC4 |
| 1151 | OFTV | ONAPIHNG FALLS TRANSPORTATION | | | SCAC3 |
| 1152 | OFWI | OLYMPIC FREIGHTWAYS INC | | | SCAC3 |
| 1153 | OFWI | ONE FIVE SEVEN THREE ZERO T | | | SCAC4 |
| 1154 | OFWJ | Oxelösund - Flen - Västmanlands Järnväg | 1876 - 1931 | S | svenska-lok.se |
| 1155 | OFWL | OTTOR FORWARDERS LTD | | | SCAC3 |
| 1156 | OFXP | OFFICE SUPPLIES EXPRESS INC | | | SCAC3 |
| 1157 | OFY | Servicios Aereos Soffly, S.A. de C.V. | Callsign: Aerosof, | MEX | AVCODES |
| 1158 | OG | Go Fly Ltd. | ICAO: GOE, Callsign: Go-Flight, IATA designator changed to GO w.e.f. 29 November 2000. | GB | AVCODES |
| 1159 | OG | Austrian Airtransport (Osterreichische Flugbetriebsgesellschaft MbH.) | ICAO: AAT, Callsign: Austrian Charter, Designator OG surrendered by Airline | A | AVCODES |
| 1160 | OG | Orientair Ltd. | | GB | AVCODES |
| 1161 | OG | Ocean Airways | ICAO: OCW, Callsign: Ocean Airways, Designator OG recalled by IATA | F | AVCODES |
| 1162 | OG | One Two Go Airlines Co. Ltd. | ICAO: OTG, IATA Prefix: 908, | T | AVCODES |
| 1163 | OG | Air Freight NZ Ltd. | ICAO: TFR, Callsign: Toll Freight, | NZ | AVCODES |
| 1164 | OG | Closed Joint-Stock Company Air Onix Airlines | ICAO: ONX, Callsign: Onixair, Ceased operations on 12 December 2013. Incorporated on 27 June 2007 | UA | AVCODES |
| 1165 | OG | Ghodawat Enterprises Pvt. Ltd. d/b/a Ghodawat Aviation | ICAO: SDG, Callsign: Hi Star, IATA designator changed to S5. | IND | AVCODES |
| 1166 | OG | Fly Play hf. | ICAO: FPY, Callsign: Player, IATA Prefix: 224, Commenced operations on 24 June 2021. | IS | AVCODES |
| 1167 | OGA | Oasis Air | Callsign: Oasis Air, | RN | AVCODES |
| 1168 | OGAM | OGAZ ONTIVEROS, MARGARITA (MX-35714 | | | SCAC4 |
| 1169 | OGAW | OGAWA ENTERPRISE TRUCK CORP | | | SCAC4 |
| 1170 | OGBA | OLIVA GARZA, BLANCA | | | SCAC4 |
| 1171 | OGBB | OGBURN, BRIAN | | | SCAC4 |
| 1172 | OGBN | OGBORN, LARRY INC | | | SCAC3 |
| 1173 | OGBN | OCEANIC GENERAL AGENCY INC | | | SCAC4 |
| 1174 | OGBO | OGLESBY BROS PETROLEUM TRANSPORTATI | | | SCAC3 |
| 1175 | OGBO | OMEGA EXPRESS | | | SCAC4 |
| 1176 | OGBR | ORGILL BROTHERS & CO INC | | | SCAC3 |
| 1177 | OGBY | OGLESBY INC | | | SCAC3 |
| 1178 | OGCB | O-G CAB CO | | | SCAC3 |
| 1179 | OGCB | OMEGA TRANSPORTATION INC | | | SCAC4 |
| 1180 | OGCL | ORANGE ACE LTD S.A | | | SCAC3 |
| 1181 | OGCL | ONE (1) CALL MOVING SOLUTIONS INC | | | SCAC4 |
| 1182 | OGCN | ORIENT GRACE CONTAINER LINE | | | SCAC4 |
| 1183 | OGCO | OK GROUP CO | | | SCAC4 |
| 1184 | OGCP | OLSON LOGISTIC SOLUTIONS INC | | | SCAC4 |
| 1185 | OGCX | The Osage Gasoline Co. | 8/1920 | | NAKINA |
| 1186 | OGCX | OSAGE GASOLINE CO. | | | PWRC |
| 1187 | OGCZ | OVERLAND GRAIN CO. | | | PWRC |
| 1188 | OGDE | OGDEN TRUCKING COMPANY | | | SCAC3 |
| 1189 | OGDI | ORINGDERFF TANKLINE INC | | | SCAC3 |
| 1190 | OGDI | ON THE GO CARGO INC | | | SCAC4 |
| 1191 | OGDM | OGDEN-MANNING EQUIPMENT CO INC | | | SCAC3 |
| 1192 | OGDS | OGDEN SHIPPING COMPANY | | | SCAC3 |
| 1193 | OGDS | OLGUIN AMEZCUA, VIVIAN LAURA CAROLI | | | SCAC4 |
| 1194 | OGE | Atlasjet Uuslararasi Havacilik A/S | IATA: 2U, Callsign: Atlasjet, IATA designator changed to KK. Name changed from Atlas International Airlines - Atlas International Havacilik A/S | TR | AVCODES |
| 1195 | OGE | Atlasjet Uuslararasi Havacilik A/S | IATA: KK, Callsign: Atlasjet, ICAO designator changed to KKK . IATA designator changed from 2U*. Name changed from Atlas International Airlines - Atlas International Havacilik A/S | TR | AVCODES |
| 1196 | OGE | OREGON GREAT EASTERN | | | PWRC |
| 1197 | OGED | OSTER, GREGORY ED | | | SCAC4 |
| 1198 | OGEE | Ogeechee Ry. Co. | added 10/1989; eliminated 1/1993; 1/1994-7/2000 | | NAKINA |
| 1199 | OGEE | Ogeechee Ry. Co. | added 10/89; eliminated 1/93; 1/94-7/2000 | | NRHS |
| 1200 | OGEE | OGEECHEE RAILWAY COMPANY | | | PWRC |
