| 1 | R | Rutland Ry. | 4/1938-4/1970 | NAKINA | |
| 2 | R | Rutland Ry. Co. | 7/1923-7/1930 | NAKINA | |
| 3 | R | Rutland R.R. Co. | 7/1932-7/1936 | NAKINA | |
| 4 | R | Rutland Ry. | 4/38-4/70 | NRHS | |
| 5 | R | RUTLAND RWY. | PWRC | ||
| 6 | R&GV | Ray & Gila Valley R.R. (Co.) | 7/1923-7/1954 | NAKINA | |
| 7 | R&GV | Ray & Gila Valley R.R. | 4/38-1/52 | NRHS | |
| 8 | R&GV | RAY & GILA VALLEY RAILROAD CO. | PWRC | ||
| 9 | R&N | Rome & Northern R.R. Co. | 8/1920 | NAKINA | |
| 10 | R&N | ROME & NORTHERN RAILROAD CO. | PWRC | ||
| 11 | R4C | Rail4Chem Eisenbahnverkehrsgesellschaft mbH | Essen | D | privat-bahn.de |
| 12 | R4C | Rail4Chem (BASF AG, Bertschi AG, HOYER GmbH, VTG-LEHNKERING AG) | D | TRAFFIC | |
| 13 | R4U | Rail4You | D | TRAFFIC | |
| 14 | RA | Red Army - Sovietunion | SU | TRAFFIC | |
| 15 | RA | REGIONALPS SA | CH | VKM | |
| 16 | RAA | Rynes Aviation | ICAO1 | ||
| 17 | RAAA | RAMIREZ, ALMA ANGELINA | SCAC4 | ||
| 18 | RAAF | RAPID AIR FREIGHT, INC | SCAC3 | ||
| 19 | RAAF | Royal Australian Air Force | AUS | TRAFFIC | |
| 20 | RAAK | RANGER TRUCKLINES INC | SCAC4 | ||
| 21 | RAAM | RAASCH, MICHAEL | SCAC3 | ||
| 22 | RAAR | RACING JLM TRANSPORT | SCAC4 | ||
| 23 | RAAS | RAMEYS AUTO SALES INC | SCAC3 | ||
| 24 | RAAT | ROAASTS TRUCKING INC | SCAC3 | ||
| 25 | RAB | DB ZugBus Regionalverkehr Alb-Bodensee | D | TRAFFIC | |
| 26 | RABA | RAB RACING LLC | SCAC4 | ||
| 27 | RABB | RAY, BOBBY TRUCKING | SCAC3 | ||
| 28 | RABB | RAY, BOBBY TRUCKING LC | SCAC4 | ||
| 29 | RABC | RABAS, CHAD EXPRESS INC | SCAC4 | ||
| 30 | RABD | REIS AUTO BODY | SCAC3 | ||
| 31 | RABD | RAJ FREIGHT SYSTEMS LTD | SCAC4 | ||
| 32 | RABE | RABE TRUCKING | SCAC3 | ||
| 33 | RABG | RADIUS LOGISTICS | SCAC4 | ||
| 34 | RABI | RED ARROW BONDED MESSENGER CORP | SCAC3 | ||
| 35 | RABK | RAZORBACK EXPRESS INC | SCAC3 | ||
| 36 | RABL | RABEL, EDWARD | SCAC3 | ||
| 37 | RABN | RABBE INC | SCAC4 | ||
| 38 | RABO | R & B DELIVERY | SCAC3 | ||
| 39 | RABP | R & B TRANSFER | SCAC3 | ||
| 40 | RABQ | RABIDEAU BROTHERS | SCAC3 | ||
| 41 | RABR | RAY BROTHERS TRANSPORTATION | SCAC3 | ||
| 42 | RABR | RAY BROTHERS TRANSPORTATION INC | SCAC4 | ||
| 43 | RABS | RAINBOW TRANSPORT | SCAC3 | ||
| 44 | RABS | RISING STAR TRANSPORT | SCAC4 | ||
| 45 | RABT | RABB BROS TRUCKING INC | SCAC3 | ||
| 46 | RABU | RABANCO COMPANIES | SCAC4 | ||
| 47 | RABW | RAINBOW EXPRESS INC | SCAC3 | ||
| 48 | RAC | Icar Air | ICAO1 | ||
| 49 | RAC | Ryukyu Air Commuter | J | TRAFFIC | |
| 50 | RACA | R A C AIR SERVICES INC | SCAC3 | ||
| 51 | RACA | Railcare | S | TRAFFIC | |
| 52 | RACB | RENT-A-COACH | SCAC3 | ||
| 53 | RACC | RATHBUN CARTAGE COMPANY, THE | SCAC3 | ||
| 54 | RACD | R & A CARRIERS INC | SCAC4 | ||
| 55 | RACF | R A C TRANSPORTATION SERVICES INC | SCAC3 | ||
| 56 | RACG | RALEIGH AIR CARGO EXPRESS INC | SCAC3 | ||
| 57 | RACG | RACING TRANSPORT | SCAC4 | ||
| 58 | RACH | RAINS, CHARLES W | SCAC3 | ||
| 59 | RACI | ROSE CITY APPLIANCE INSTALLATION | SCAC3 | ||
| 60 | RACJ | RACING ACERS | SCAC4 | ||
| 61 | RACK | RACK TRANSPORT CO INC | SCAC3 | ||
| 62 | RACL | RACINE, GEORGES LES ENTERPRISES | SCAC3 | ||
| 63 | RACM | R AND C RANCHES LLC | SCAC4 | ||
| 64 | RACN | Raccoon River R.R. Co. | added 7/1981; eliminated 4/1982 | NAKINA | |
| 65 | RACN | Raccoon River R.R. Co. | added 7/81; eliminated 4/82 | NRHS | |
| 66 | RACN | RACCOON RIVER RAILROAD | PWRC | ||
| 67 | RACN | Raccoon River Railroad | RSRV | ||
| 68 | RACN | RACE INC | SCAC4 | ||
| 69 | RACO | RARITAN CONTAINER CO INC | SCAC3 | ||
| 70 | RACO | RICH AND CO | SCAC4 | ||
| 71 | RACP | RAC TRANSPORT COMPANY, INC | SCAC3 | ||
| 72 | RACP | RAC TRANSPORT CO | SCAC4 | ||
| 73 | RACQ | RED ARROW CORPORATION | SCAC3 | ||
| 74 | RACR | RACERS GROUP, THE | SCAC4 | ||
| 75 | RACS | RACCO EXPRESS INC | SCAC3 | ||
| 76 | RACT | ROYCE AYR CUTTING TOOLS INC | SCAC4 | ||
| 77 | RACU | ACCIONA LOGISTICA | SCAC4 | ||
| 78 | RACV | RAMCO TRUCKING INC | SCAC4 | ||
| 79 | RACW | RALCO CORPORATION | SCAC3 | ||
| 80 | RACX | General Electric Rail Services Corp. | added 1/2000; 7/2000-7/2005 | NAKINA | |
| 81 | RACX | General Electric Railcar Services Corp. | added 10/1995; eliminated 1/2000 | NAKINA | |
| 82 | RACX | Railway Accessories Co. | 10/1966; eliminated 10/1967 | NAKINA | |
| 83 | RACX | Railway Accessories Co. (J.L. Ortner) | 1/1943-7/1965 | NAKINA | |
| 84 | RACX | Railway Accessories Co. (J.L. Ortner) | 1/52-7/65 | NRHS | |
| 85 | RACX | Railway Accessories Co. | 10/66; eliminated 10/67 | NRHS | |
| 86 | RACX | General Electric Railcar Services Corp. | added 10/95; eliminated 1/2000 | NRHS | |
| 87 | RACX | General Electric Rail Services Corp. | added 1/2000; 7/2000 | NRHS | |
| 88 | RACX | *RAILWAY ACCESSORIES CO. | PWRC | ||
| 89 | RACX | +GENERAL ELECTRIC RAIL SERVICES CORPORATION | PWRC | ||
| 90 | RACX | General Electric Rail Services Corporation | RSRV | ||
| 91 | RACX | RAILWAY ACCESSORIES CO | SCAC3 | ||
| 92 | RACY | REYNOLDS ASPHALT & CONSTRUCTION COM | SCAC4 | ||
| 93 | RAD | Alada | ICAO1 | ||
| 94 | RADA | RANCOURT, DANIEL L | SCAC4 | ||
| 95 | RADB | RADONICH BROTHERS TRUCKING | SCAC3 | ||
| 96 | RADC | RAPID DELIVERY CO | SCAC3 | ||
| 97 | RADD | RAY, DON DRIVE-A-WAY COMPANY INC | SCAC3 | ||
| 98 | RADD | RAD TECHNOLOGIES INC | SCAC4 | ||
| 99 | RADF | RADFORDS EXPRESS, INC | SCAC3 | ||
| 100 | RADG | RAD FREIGHT LINES | SCAC3 |