| 1 | RTS | Relief Transport Services Ltd. | Callsign: Relief, | GB | AVCODES |
| 2 | RTS | Relief Transport Services | | | ICAO1 |
| 3 | RTS | Rail Transport Service Germany GmbH | München (Ableger von RTS Austria - Swietelsky) | D | privat-bahn.de |
| 4 | RTS | RICHARDS TRANSPORTATION SERVICE INC | | | SCAC4 |
| 5 | RTS | Rail Transport Service GmbH | | A | TRAFFIC |
| 6 | RTS | RTS Rail Transport Service GmbH | | AT | VKM |
| 7 | RTSA | RIVERSIDE TRUCK & STORAGE CO | | | SCAC3 |
| 8 | RTSA | Rail Technical Support | Real: rts | AUS | TRAFFIC |
| 9 | RTSB | RELIABLE TRANSPORTATION SOLUTIONS L | | | SCAC4 |
| 10 | RTSC | RILEY TRUCKING SERVICE INC | | | SCAC3 |
| 11 | RTSC | RTS | | | SCAC4 |
| 12 | RTSC | RTS Rail Traction Services (Switzerland) AG | Real: RTS | CH | TRAFFIC |
| 13 | RTSD | R T S TRUCKING LLC | | | SCAC4 |
| 14 | RTSE | RTS ENTERPRISES | | | SCAC3 |
| 15 | RTSF | RUTLAND TOOL SERVICE INC | | | SCAC3 |
| 16 | RTSF | RUSSELLS TREE & SHRUB FARM LLC | | | SCAC4 |
| 17 | RTSH | RT SYSTEMS INC | | | SCAC3 |
| 18 | RTSI | ROBINHOOD TOWING SERVICE | | | SCAC3 |
| 19 | RTSI | ROBINHOOD TOWING SERVICE | | | SCAC4 |
| 20 | RTSJ | R T S TRANSPORTATION INC | | | SCAC3 |
| 21 | RTSK | RUST & SONS TRUCKING INC | | | SCAC4 |
| 22 | RTSL | RICHARDSON TRANSPORT LTD | | | SCAC3 |
| 23 | RTSM | RTS TRANSPORTATION SYSTEMS INC | | | SCAC3 |
| 24 | RTSN | RTS INVESTMENT CORPORATION | | | SCAC3 |
| 25 | RTSN | REAVES TRANSPORTATION SERVICES LLC | | | SCAC4 |
| 26 | RTSO | RAINS TRUCKING SERVICE INC | | | SCAC3 |
| 27 | RTSQ | RAPID TRANSFER & STORAGE CO | | | SCAC3 |
| 28 | RTSQ | RAPID TRANSFER & STORAGE CO | | | SCAC4 |
| 29 | RTSR | Rail Transportation Services, Inc. | added 7/1996 | | NAKINA |
| 30 | RTSR | Rail Transportation Services, Inc. | added 7/96 | | NRHS |
| 31 | RTSR | RAIL TRANSPORTATION SERVICES, INC. | | | PWRC |
| 32 | RTSR | RICHMOND TRAFFIC SERVICES INC | | | SCAC3 |
| 33 | RTSRC | Regional Transit Service | in Riverside, California | USA | TRAFFIC |
| 34 | RTSS | ROADCO TRANSPORTATION SERVICES, INC. | | | SCAC3 |
| 35 | RTSS | ROADCO TRANSPORTATION SERVICES INC | | | SCAC4 |
| 36 | RTST | ROOTS TRANSFER INC | | | SCAC3 |
| 37 | RTSU | ROBERT KUKLA GMBH | | D | BIC |
| 38 | RTSU | RENT TANK AG | | | SCAC3 |
| 39 | RTSU | ROBERT KUKLA GMBH | | | SCAC4 |
| 40 | RTSW | RAM TRANS SYSTEMS INC | | | SCAC3 |
| 41 | RTSW | R T S | | | SCAC4 |
| 42 | RTSX | Rail Transportation Services Inc. | 7/2000; eliminated 10/2002; 7/2005 (not listed) | | NAKINA |
| 43 | RTSX | Rail Transportation Services Inc. | Jul-00 | | NRHS |
| 44 | RTSX | RAIL TRANSPORTATION SERVICES, INC. | | | PWRC |
| 45 | RTSX | Rail Transportation Services | | | RSRV |
| 46 | RTSY | RAM TRANSPORT SYSTEMS INC | | | SCAC3 |
| 47 | RTSY | RTS MOVING SERVICES | | | SCAC4 |
