| 1 | ROA | Reno Air, Inc. | IATA: QQ, Callsign: Reno Air, Merged in American Airlines | USA | AVCODES |
| 2 | ROA | Roland Air Flugverkehrs und Vertriebsgesellschaft mbH | IATA: DU, Callsign: Roland Air, | D | AVCODES |
| 3 | ROA | Atom Airways | Callsign: Atomways, | RO | AVCODES |
| 4 | ROA | Reno Air | IATA: QQ | | ICAO1 |
| 5 | ROAA | ROADEX SERVICES LTD | | | SCAC4 |
| 6 | ROAB | ROBBINS, ALLAN B | | | SCAC3 |
| 7 | ROAB | ROGERS FARM SUPPLY | | | SCAC4 |
| 8 | ROAC | Romanian Air Corps | Real: RAC, The Romanian Air Corps or Aviation Corps (RAC) (Romanian: Corpul de Aviație) was the air arm of the Romanian army until the formation of the Romanian Air Force in 1924 | RO | TRAFFIC |
| 9 | ROAD | ROAD COMMERCE CORPORATION | | | PWRC |
| 10 | ROAD | ROAD COMMERCE CORPORATION | | | SCAC3 |
| 11 | ROAD | ROAD LINK XPRESS | | | SCAC4 |
| 12 | ROADR | Roadrunner | City: Harlow | GB | TRAFFIC |
| 13 | ROAE | ROSS, A J LOGISTICS INC | | | SCAC3 |
| 14 | ROAE | ROAD RUNNER TRUCKING | | | SCAC4 |
| 15 | ROAF | ROAD AMERICAN FREIGHT SYSTEMS INC | | | SCAC3 |
| 16 | ROAF | Romanian Air Force | | RO | TRAFFIC |
| 17 | ROAG | ROWLAND, LONNIE TRUCKING | | | SCAC3 |
| 18 | ROAJ | ROADAIR LEASING INC | | | SCAC3 |
| 19 | ROAK | ROADKINS TRUCKING CORP | | | SCAC3 |
| 20 | ROAL | ROANE TRANSPORTATION SERVICES LLC | | | SCAC4 |
| 21 | ROAM | ROADMAS | | | SCAC4 |
| 22 | ROAN | ROANS TRUCKING SERVICE | | | SCAC3 |
| 23 | ROAN | ROANE LOGISTICS INC | | | SCAC4 |
| 24 | ROAO | ROARING EXPRESS CO INC | | | SCAC3 |
| 25 | ROAO | ROBERT FILM SERVICES INC | | | SCAC4 |
| 26 | ROAP | ROAP TRANSPORT INC | | | SCAC3 |
| 27 | ROAQ | ROAYL TRUCKING CO | | | SCAC3 |
| 28 | ROAR | ROAD AND RAIL TRUCKING COMPANY | | | PWRC |
| 29 | ROAR | ROAR LOGISTICS INC | | | SCAC4 |
| 30 | ROAT | ROES STAIR CO | | | SCAC4 |
| 31 | ROAU | ROAM GLOBAL SOLUTIONS LLC | | USA | BIC |
| 32 | ROAW | ROBINSON AND WILLIAMS TRANSPORT INC | | | SCAC3 |
| 33 | ROAY | ROAD-CON SYSTEMS INC | | | SCAC3 |
