| 1 | RSM | Air Somalia | Callsign: Air Somalia, Founded in 2001. Ceased operations. | SO | AVCODES |
| 2 | RSM | Royal Star Aviation Inc. | Callsign: Royal Star, | RP | AVCODES |
| 3 | RSM | Air Somalia | | | ICAO1 |
| 4 | RSM | Railroad Switching Service of Missouri, Inc. | added 10/1989; eliminated 7/1991; 1/1994-7/2005 | | NAKINA |
| 5 | RSM | Railroad Switching Service of Missouri, Inc. | added 10/89; eliminated 7/91; 1/94-7/2000 | | NRHS |
| 6 | RSM | RAILROAD SWITCHING SERVICE OF MISSOURI, INC. | | | PWRC |
| 7 | RSM | Railroad Switching Service of Missouri | | | RSRV |
| 8 | RSMB | RODRIGUEZ SANTA MARIA, ROBERTO | | | SCAC4 |
| 9 | RSMC | ROSE MARIE INCORPORATED | | | SCAC4 |
| 10 | RSMD | ROSE, MICHAEL DAMON | | | SCAC3 |
| 11 | RSMD | ROSEMAR LIMITED | | | SCAC4 |
| 12 | RSME | RASMUSSEN MANAGEMENT | | | SCAC3 |
| 13 | RSMG | RS MOVING & STORAGE SOLUTIONS INC | | | SCAC4 |
| 14 | RSMH | RAIL SCALE MINIATURES | | | SCAC4 |
| 15 | RSMK | R SAN MIGUEL TRUCKING | | | SCAC4 |
| 16 | RSMM | RUSHMORE TRANSPORTATION LTD | | | SCAC4 |
| 17 | RSMN | ROSEMONT TRANSPORT INC | | | SCAC4 |
| 18 | RSMO | ROSE MOVING & STG CO INC | | | SCAC3 |
| 19 | RSMO | ROSE MOVING & STORAGE CO INC | | | SCAC4 |
| 20 | RSMP | RUSMIN TRUCKING | | | SCAC3 |
| 21 | RSMP | RS MOTORSPORTS | | | SCAC4 |
| 22 | RSMQ | RASMUSSEN SERVICE INC | | | SCAC3 |
| 23 | RSMQ | ROSAS, M TRANSPORT | | | SCAC4 |
| 24 | RSMS | ROUSH MOVING & STORAGE CO | | | SCAC3 |
| 25 | RSMT | R S M TRANSPORT INC | | | SCAC3 |
| 26 | RSMT | ROSS MARITIME INC | | | SCAC4 |
| 27 | RSMU | REMUS MARINE CO., INC. | | | SCAC3 |
| 28 | RSMW | RED SEA MARINE C/O NORDIC MARITIME | | | SCAC4 |
| 29 | RSMY | R S M TRUCKING LLC | | | SCAC4 |
