| 1 | RM | Air Moldova International, S.A. | ICAO: MLV, Callsign: Moldova International, IATA Prefix: 283, Designator RM recalled by IATA | MD | AVCODES |
| 2 | RM | McAlpine Aviation | ICAO: MAL, Callsign: Mcalpine, | GB | AVCODES |
| 3 | RM | Rotterdamse Luchtvaart Expoeditie Maatschappik | | NL | AVCODES |
| 4 | RM | Regional Air Ltd | Designator RM* recalled by IATA | EAK | AVCODES |
| 5 | RM | Aircompany Armenia LLC | ICAO: NGT, Callsign: Nika, | AM | AVCODES |
| 6 | RM | RIMA Rio Madeira Aerotáxi Ltda | IATA Designator chanegd to R8. | BR | AVCODES |
| 7 | RM | | | I | TRAFFIC |
| 8 | RM | Rallarmålarna AB | | SE | VKM |
| 9 | RMA | Rocky Mountain Airways | IATA: JC, Callsign: Rocky Mountain, Merged into Britt Airways to form Continental Express during 1991. Founded in 1963. Commenced operations in 1965. | USA | AVCODES |
| 10 | RMA | Rocky Mountain Airways | Callsign: Rocky Mountain, | USA | AVCODES |
| 11 | RMA | Rocky Mountain Airways | | | ICAO1 |
| 12 | RMAA | RAMZA INC | | | SCAC4 |
| 13 | RMAB | RODRIGUEZ, M TRANSPORTATION | | | SCAC4 |
| 14 | RMAC | ROMA CORPORATION | | | SCAC3 |
| 15 | RMAG | ROLAND MARKETING | | | SCAC4 |
| 16 | RMAH | R & M TRANSPORT INC | | | SCAC4 |
| 17 | RMAI | ROSS MACHINE & IRON WORKS INC | | | SCAC4 |
| 18 | RMAIL | Royal Main | | GB | TRAFFIC |
| 19 | RMAJ | RODRIGUEZ, MIGUEL ANGEL | | | SCAC4 |
| 20 | RMAK | ROMA TRANSPORT INC | | | SCAC3 |
| 21 | RMAL | REYES, MARIVEL | | | SCAC4 |
| 22 | RMAN | ROMANS TRANSPORTATION INC | | | SCAC3 |
| 23 | RMAN | RAMAN TRUCKING | | | SCAC4 |
| 24 | RMAQ | ROMA FOOD ENTERPRISES | | | SCAC3 |
| 25 | RMAQ | ROMA FOOD ENTERPRISES INC (VISTAR C | | | SCAC4 |
| 26 | RMAR | RAILMAR AGENCY LTD, s.r.o. | | CZ | VKM |
| 27 | RMAS | RAMIREZ & SONS | | | SCAC3 |
| 28 | RMAT | ROMA TRANSPORT SERVICE INC | | | SCAC3 |
| 29 | RMAV | R M I GLOBAL LOGISTICS INC | | | SCAC4 |
| 30 | RMAW | REM MARITIME AS | | | SCAC4 |
| 31 | RMAX | Rocky Mountain Rail Society | 7/2000-7/2005 (not listed) | | NAKINA |
| 32 | RMAX | American Refrigerator Transit Co. | added 4/1956; 10/1957-4/1970; eliminated 4/1974; 1/1975-1/1980 | | NAKINA |
| 33 | RMAX | American Refrigerator Transit Co. | 10/57-4/70; eliminated 4/74; 1/75-1/80 | | NRHS |
| 34 | RMAX | Rocky Mountain Rail Society | Jul-00 | | NRHS |
| 35 | RMAX | *AMERICAN REFRIGERATOR TRANSIT CO. | | | PWRC |
| 36 | RMAX | +ROCKY MOUNTAIN RAIL SOCIETY | | | PWRC |
| 37 | RMAX | Rocky Mountain Rail Society | | | RSRV |
| 38 | RMAX | ROCKY MOUNTAIN RAIL SOCIETY | | | SCAC4 |
| 39 | RMAY | REMINGTON MOVING AND STORAGE | | | SCAC4 |
| 40 | RMB | Routemaster Buses Ltd. | | GB | TRAFFIC |
| 41 | RMBA | RUMBA SHIPPING LIMITED | | | SCAC3 |
| 42 | RMBA | RMT TRANSPORT LLC | | | SCAC4 |
| 43 | RMBC | RAMSDE | | | SCAC4 |
| 44 | RMBC | RMB Club | | USA | TRAFFIC |
| 45 | RMBD | RAMBAUD INTERNATIONAL | | | SCAC3 |
| 46 | RMBD | RELIABLE METAL BUILDINGS LTD | | | SCAC4 |
| 47 | RMBE | R M B ENTERPRISES INC | | | SCAC4 |
| 48 | RMBF | RMB OILFIELD SERVICES | | | SCAC4 |
| 49 | RMBH | ROSIE MOBILE HOME TOWING INC | | | SCAC3 |
| 50 | RMBI | R & M LOGISTICS LLC | | | SCAC4 |
| 51 | RMBK | RUMBLE TRUCKING & LOGISTICS INC | | | SCAC4 |
| 52 | RMBL | RAMIREZ, BLANCA E | | | SCAC4 |
| 53 | RMBM | RA ELLS MOBILE MOVING | | | SCAC3 |
| 54 | RMBN | RAMBONE TRUCKING CO INC | | | SCAC3 |
| 55 | RMBN | RMF SOLUTIONS | | | SCAC4 |
| 56 | RMBO | RAMBO REEFER SERVICES | | | SCAC3 |
| 57 | RMBP | ROCKY MOUNTAIN BRAKE SUPPLY INC | | | SCAC4 |
| 58 | RMBQ | RMB CORP | | | SCAC3 |
| 59 | RMBR | RAMBLER TRUCKING INC | | | SCAC3 |
| 60 | RMBS | REINER BROS INC | | | SCAC3 |
| 61 | RMBS | RMB SHIPPING BV | | | SCAC4 |
| 62 | RMBT | ROMNEY, BUCK TRUCKING | | | SCAC3 |
| 63 | RMBT | ROMNEY, BUCK TRUCKING | | | SCAC4 |
| 64 | RMBX | American Refrigerator Transit Co. | added 7/1962; 7/1965-4/1970; eliminated 4/1972 | | NAKINA |
| 65 | RMBX | American Refrigerator Transit Co. | 7/65-4/70; eliminated 4/72 | | NRHS |
| 66 | RMBX | AMERICAN REFRIGERATOR TRANSIT CO. | | | PWRC |
| 67 | RMC | RMC Group Services Ltd. | Callsign: Readymix, | GB | AVCODES |
| 68 | RMCB | RICCOBENE MASONRY CO INC | | | SCAC4 |
| 69 | RMCC | R M C CORPORATION | | | SCAC3 |
| 70 | RMCC | RM CLASSIC CARS | | | SCAC4 |
| 71 | RMCD | ROMARCO CORPORATION | | | SCAC3 |
| 72 | RMCD | RMC TRANSPORTATION INC | | | SCAC4 |
| 73 | RMCF | ROCKY MOUNTAIN CONTRACTORS INC | | | SCAC4 |
| 74 | RMCG | RICHE, MAURICE G | | | SCAC3 |
| 75 | RMCG | REMLINGER MANUFACTURING CO INC | | | SCAC4 |
| 76 | RMCH | RAMCO TRUCKING INC | | | SCAC3 |
| 77 | RMCH | RM: Regionalverkehr Mittelland AG | Real: RM | CH | TRAFFIC |
| 78 | RMCI | RAIL MARINE CONTAINER TRANSPORT INC | | | SCAC3 |
| 79 | RMCL | RAMOS, CARLOS TRUCKING INC | | | SCAC3 |
| 80 | RMCM | R M C TRUCKING INC | | | SCAC3 |
| 81 | RMCM | RMC INC | | | SCAC4 |
| 82 | RMCO | RMC TRANSPORTATION INC | | | SCAC3 |
| 83 | RMCP | RAMCO TRUCKING INC | | | SCAC3 |
| 84 | RMCQ | R M CARTAGE INC | | | SCAC3 |
| 85 | RMCR | REMCO TRANSPORTATION CO INC | | | SCAC3 |
| 86 | RMCS | RIMARC TRANSPORTATION INC | | | SCAC4 |
| 87 | RMCU | MULTISTAR LEASING LTD | | GB | BIC |
| 88 | RMCU | RMC (TRANCOLEASING) LTD. | | | PWRC |
| 89 | RMCU | RMC Trancoleasing | | | RSRV |
| 90 | RMCU | REYNOLDS METALS COMPANY | | | SCAC3 |
| 91 | RMCU | MULTISTAR LEASING LIMITED | | | SCAC4 |
| 92 | RMCW | RICHWOOD MEAT COMPANY | | | SCAC4 |
| 93 | RMCX | Aluminum Co. of America | added 1/2009 | | NAKINA |
| 94 | RMCX | Reynolds Metals Co. | added 4/1969; 4/1970-7/2005; eliminated 10/2006; added 7/2007; eliminated 1/2009 | | NAKINA |
| 95 | RMCX | Reade Manufacturing Co., Inc. | 7/1954 (not listed); added 7/1955; 10/1957-4/1961; eliminated 10/1964 | | NAKINA |
| 96 | RMCX | Reid, Murdoch, a Division of Consolidated Grocers Corp. | 4/1947-1/1950 | | NAKINA |
| 97 | RMCX | Reid, Murdoch & Co. | 7/1935-1/1946 | | NAKINA |
| 98 | RMCX | Reid, Murdoch & Co. | Apr-38 | | NRHS |
| 99 | RMCX | Reade Manufacturing Co., Inc. | added 7/55; 10/57-4/61 | | NRHS |
| 100 | RMCX | Reynolds Metals Co. | added 4/69; 4/70-7/2000 | | NRHS |
