| 6101 | RMMT | ROMAN SC INC | | | SCAC4 |
| 6102 | RMMU | EMERSON CLIMATE TECHNOLOGIES | | DK | BIC |
| 6103 | RMMU | YORK REFRIGERATION MARINE AND CONTR | | | SCAC4 |
| 6104 | RMMV | RAYS MACHINERY MOVERS | | | SCAC3 |
| 6105 | RMMX | The Andersons-Rail Group | added 10/2004; 7/2005 | | NAKINA |
| 6106 | RMMX | Railcar, Ltd. | added 4/1994; 7/2000; eliminated 10/2004 | | NAKINA |
| 6107 | RMMX | Railcar, Ltd. | added 4/94; 7/2000 | | NRHS |
| 6108 | RMMX | THE ANDERSONS-RAIL GROUP [(RMGX) RAILCAR LIMITED] | | | PWRC |
| 6109 | RMMX | Railcar Limited | | | RSRV |
| 6110 | RMMX | ANDERSONS INC, THE | | | SCAC4 |
| 6111 | RMN | RM Aviation Ltd. | Callsign: Roman, | GB | AVCODES |
| 6112 | RMN | Classic Flight Training Services Ltd | Callsign: Rainman, Ceased operations. | GB | AVCODES |
| 6113 | RMNC | ROCKY MOUNTAIN COMPANY | | | SCAC3 |
| 6114 | RMNC | RMC FOODS INC | | | SCAC4 |
| 6115 | RMND | RAMSAN | | | SCAC4 |
| 6116 | RMNG | R & M TRUCKING | | | SCAC3 |
| 6117 | RMNG | RM TRUCKING INC | | | SCAC4 |
| 6118 | RMNI | ROMAIN TRANSPORT | | | SCAC4 |
| 6119 | RMNL | RUEBUSH, LARRY TRUCKING INC | | | SCAC3 |
| 6120 | RMNL | RAMOS, MANUEL A | | | SCAC4 |
| 6121 | RMNR | RMS TRANSPORT | | | SCAC4 |
| 6122 | RMNS | R M TRUCKING & STORAGE | | | SCAC4 |
| 6123 | RMNT | RICHMOND TRANSPORT INC | | | SCAC3 |
| 6124 | RMNY | ROMNEY BENTLEY, RULON KENT | | | SCAC4 |
| 6125 | RMNZ | CSX TRANSPORTATION, INC. | | | PWRC |
| 6126 | RMO | Rybinsk Motors, Joint-Stock Company | Callsign: Rybmotors, | RUS | AVCODES |
| 6127 | RMO | Arm-Aero | Callsign: Arm-Aero, | AM | AVCODES |
| 6128 | RMO | Arm-Aero | | | ICAO1 |
| 6129 | RMOA | ROMA | | | SCAC4 |
| 6130 | RMOB | RUSS'S MOBILE HOME SERVICE | | | SCAC3 |
| 6131 | RMOB | REDBIRD MOTOR | | | SCAC4 |
| 6132 | RMOC | RAMSEY OIL CO INC | | | SCAC3 |
| 6133 | RMOD | ROBALI MOTORSPORTS | | | SCAC4 |
| 6134 | RMOI | R & M OIL & SUPPLY INC | | | SCAC4 |
| 6135 | RMOL | ROMINE OIL | | | SCAC3 |
| 6136 | RMOL | ROMINE OIL COMPANY | | | SCAC4 |
| 6137 | RMOM | RACHLES/MI | | | SCAC4 |
| 6138 | RMON | RAINBOW MOVING AND STORAGE INC | | | SCAC4 |
| 6139 | RMOO | RAMCON TRANSPORTATION | | | SCAC4 |
| 6140 | RMOP | REMO ENTERPRISE INC OF LIBERIA | | | SCAC3 |
| 6141 | RMOQ | RMORMES TRANSPORTATION INC | | | SCAC3 |
| 6142 | RMOR | ROMA TRANSPORT INC | | | SCAC4 |
| 6143 | RMOS | RAMOS TRUCK LINE | | | SCAC3 |
| 6144 | RMOT | RILEY MOTORSPORTS | | | SCAC4 |
| 6145 | RMOV | RAMOS MOVERS INC | | | SCAC3 |
| 6146 | RMP | Servicios de Rampa Y Mostrador, S.A. de C.V. | Callsign: Seramsa, | MEX | AVCODES |
| 6147 | RMP | Servicios De Rampa Y Mostrador | | | ICAO1 |
| 6148 | RMPA | R M P & ASSOCIATES INC | | | SCAC3 |
| 6149 | RMPATP5 | | City: Rostov | RUS | TRAFFIC |
| 6150 | RMPB | RELATIONSHIPS MATTER PUBLISHING INC | | | SCAC4 |
| 6151 | RMPD | RATION MAKER PRODUCTS SOUTH INC | | | SCAC3 |
| 6152 | RMPD | RH MFG / PEDRO ZARAGOZA | | | SCAC4 |
| 6153 | RMPE | RAPTOR MINING PRODUCTS INC | | | SCAC4 |
| 6154 | RMPG | RAMPAGE ENTERPRISES INC | | | SCAC4 |
| 6155 | RMPN | ROMERO PENA, FRANCISCO (MX-469948) | | | SCAC4 |
| 6156 | RMPQ | REGIONAL MUNICIPALITY OF PEEL | | | SCAC3 |
| 6157 | RMPQ | ROCKY MOUNTAIN PROPANE EXPRESS INC | | | SCAC4 |
| 6158 | RMPR | RAMSEY PISTON RING CO | | | SCAC3 |
| 6159 | RMPR | RM PRODUCE | | | SCAC4 |
| 6160 | RMPS | RAMPLA SHIPPING COMPANY LIMITED | | | SCAC3 |
| 6161 | RMPS | ROMA EXPRESS | | | SCAC4 |
| 6162 | RMPV | RAM TRANSPORTATION SERVICES INC | | | SCAC4 |
| 6163 | RMPX | Progress Rail Services Corp. | added 10/2004; 7/2005 | | NAKINA |
| 6164 | RMPX | Railcar, Ltd. | added 4/2000; 7/2000; eliminated 10/2004 | | NAKINA |
| 6165 | RMPX | Railcar, Ltd. | added 4/2000; 7/2000 | | NRHS |
| 6166 | RMPX | PROGRESS RAIL SERVICES CORP. [RAILCAR, LTD.] | | | PWRC |
| 6167 | RMPX | Progress Rail Services Corporation (Railcar Ltd) | | | RSRV |
| 6168 | RMPX | PROGRESS RAIL SERVICES CORPORATION | | | SCAC4 |
| 6169 | RMPY | RIMPYS TRANSPORT LTD | | | SCAC4 |
| 6170 | RMPZ | *READY MIX PLANT | | | PWRC |
| 6171 | RMPZ | *TRANSAMERICA LEASING INC [(REAZ) MISSOURI PACIFIC RAILROAD] | | | PWRC |
| 6172 | RMPZ | TAL International | | | RSRV |
| 6173 | RMPZ | TRANSAMERICA LEASING, INC. | | | SCAC4 |
| 6174 | RMQ | Air Armorique | Callsign: Airmorique, | F | AVCODES |
| 6175 | RMQF | R & M FARMS | | | SCAC4 |
| 6176 | RMQN | RAMTIN COMPANY S A | | | SCAC3 |
| 6177 | RMQT | RACINE, MAX TRUCKING | | | SCAC3 |
| 6178 | RMQT | RAM TRANSPORT | | | SCAC4 |
| 6179 | RMR | Romaero Ltd. | Callsign: Romaero, | RO | AVCODES |
| 6180 | RMRA | RADIATEUR MONTREAL RADIATOR INC | | | SCAC4 |
| 6181 | RMRB | RIEMER BROS INC | | | SCAC3 |
| 6182 | RMRB | RAMIREZ BROS | | | SCAC4 |
| 6183 | RMRD | RAM ROD TRUCKING & STORAGE INC | | | SCAC3 |
| 6184 | RMRD | ROMERO, MARISCOS | | | SCAC4 |
| 6185 | RMRF | REIMER FARM SUPPLIES LTD | | | SCAC3 |
| 6186 | RMRG | RICHARDS, MARK RACING | | | SCAC4 |
| 6187 | RMRI | R & M TRANSPORTS INC | | | SCAC3 |
| 6188 | RMRI | R M EXPRESS INC | | | SCAC4 |
| 6189 | RMRO | RAM ROD TRUCKING | | | SCAC3 |
| 6190 | RMRP | RO-MAR TRANSPORTATION SYSTEMS, INC | | | SCAC3 |
| 6191 | RMRP | RO-MAR TRANSPORTATION SYSTEMS INC | | | SCAC4 |
| 6192 | RMRR | Rocky Mountain Railcar and R.R., Inc. | added 10/1987; eliminated 1/1991; added 10/1991; 1/1994; eliminated 1/1997; 7/2000-7/2005 | | NAKINA |
| 6193 | RMRR | Rocky Mountain Railcar and R.R., Inc. | added 10/87; eliminated 1/91; added 10/91; 1/94; eliminated 1/97; 7/2000 | | NRHS |
| 6194 | RMRR | ROCKY MOUNTAIN RAILCAR & RAILROAD, INC | | | PWRC |
| 6195 | RMRR | Rocky Mountain Railcar and Railroad | | | RSRV |
| 6196 | RMRR | ROCKY MOUNTAIN RAILCAR AND RAILROAD | | | SCAC3 |
| 6197 | RMRS | RAMAPO ROADWAY SERVICES CO INC | | | SCAC3 |
| 6198 | RMRT | RAMROD TRUCKING INC | | | SCAC3 |
| 6199 | RMRW | ROCKY MOUNTAIN RECREATION TOURS (20 | | | SCAC4 |
| 6200 | RMRX | Rocky Mountain Railtours | 7/2005 (not listed) | | NAKINA |
