| 1 | SR | Swiss Air Transport Co. Ltd. (Swissair) | ICAO: SWR, Callsign: Swissair, IATA Prefix: 085, Ceased Operations on 31 March 2002. | CH | AVCODES |
| 2 | SR | Sundair GmbH | ICAO: SDR, Callsign: Sundair, Commenced operations on 27 September 2017. | D | AVCODES |
| 3 | SR | SouthRail Corp. | added 7/1988; 1/1994; eliminated 7/1994 | | NAKINA |
| 4 | SR | Kansas City Southern Ry. Co. | added 7/1994; 7/2000-7/2005 | | NAKINA |
| 5 | SR | SouthRail Corp. | added 7/88; 1/94; eliminated 7/94 | | NRHS |
| 6 | SR | Kansas City Southern Ry. Co. | added 7/94; 7/2000 | | NRHS |
| 7 | SR | KANSAS CITY SOUTHERN RAILWAY COMPANY [SOUTHRAIL CORPORATION] | | | PWRC |
| 8 | SR | Southrail Corp. (Kansas City Southern Railway) | | | RSRV |
| 9 | SR | SOUTHRAIL CORPORATION | | | SCAC4 |
| 10 | SR | Southern Railway | From the merger of the London and South Western Railway, London Brighton and South Coast Railway and South Eastern and Chatham Railway | GB | TRAFFIC |
| 11 | SR | ScotRail Railways | | UK | VKM |
| 12 | SRA | Sair Aviation (FAA) | Callsign: Sair, | CDN | AVCODES |
| 13 | SRA | Sprintair Kaunus | Callsign: Sprintair Kaunus, | LT | AVCODES |
| 14 | SRA | Sarah Airways | | MA | AVCODES |
| 15 | SRA | Saudi Royal Aviation | Callsign: Saudi Arabian, | SA | AVCODES |
| 16 | SRA | Sair Aviation | | | ICAO1 |
| 17 | SRA | State Rail Authority of New South Wales | | AUS | TRAFFIC |
| 18 | SRAA | SILVERLINE CARRIERS INC | | | SCAC4 |
| 19 | SRAB | SELECCIONAD | | | SCAC4 |
| 20 | SRAD | SLOAN PETROLEUM TRANSPORT LLC | | | SCAC4 |
| 21 | SRAE | SRS ENTERTAINMENT INC | | | SCAC4 |
| 22 | SRAF | STRATFORD TRUCKING SERVICE INC | | | SCAC4 |
| 23 | SRAF | Southern Rhodesia Air Force | | RHO | TRAFFIC |
| 24 | SRAG | SANRAM TRANSPORT INC | | | SCAC4 |
| 25 | SRAIL | Stahlberg Roensch GmbH | | DE | VKM |
| 26 | SRAJ | SANCHEZ RODRIGUEZ, ANTONIO JAVIER | | | SCAC4 |
| 27 | SRAK | SPANISH RIVER NURSERY INC. | | | SCAC4 |
| 28 | SRAL | SORENSEN, RANDY TRUCKING | | | SCAC4 |
| 29 | SRAN | SIERRA INC | | | SCAC4 |
| 30 | SRAO | SOUTH CALIFORNIA TRANSPORTATION INC | | | SCAC4 |
| 31 | SRAP | STRABER OIL CO INC | | | SCAC4 |
| 32 | SRAS | STRATO TRANSPORT INC | | | SCAC4 |
| 33 | SRAT | SCRANTON TRANSFER, INC | | | SCAC1 |
| 34 | SRAU | ENDEL SRA | | F | BIC |
| 35 | SRAU | SRA SAVAC | | | SCAC4 |
| 36 | SRAV | SEARSONS, THE | | | SCAC4 |
| 37 | SRAW | SIERRA WEST EXPRESS | | | SCAC1 |
| 38 | SRAX | The State Refining Association | 8/1920 | | NAKINA |
| 39 | SRAX | Southern Rail Associates Inc. | added 7/2002; 7/2005 | | NAKINA |
| 40 | SRAX | *STATE REFINING ASSOCIATION | | | PWRC |
| 41 | SRAX | +SOUTHERN RAIL ASSOCIATES INC. | | | PWRC |
| 42 | SRAX | Southern Rail Associates | | | RSRV |
| 43 | SRAX | SOUTHERN RAIL ASSOCIATES INC | | | SCAC4 |
| 44 | SRAX | Southern Rail Associates Inc. | | USA | TRAFFIC |
| 45 | SRAY | ST ROSE NURSERY | | | SCAC4 |
| 46 | SRB | Serb Air | Callsign: Air Serb, | BIH | AVCODES |
| 47 | SRB | Solar Aviation Co. Ltd. | Callsign: Solar Thai, | T | AVCODES |
| 48 | SRB | Serbian Air Force | Callsign: Serbian Air Force, | SR | AVCODES |
| 49 | SRB | Südburgenländische Regionalbahn | | A | TRAFFIC |
| 50 | SRB | Südburgenländische Regionalbahn | | AT | VKM |
| 51 | SRBA | STAR BULK | | | SCAC4 |
| 52 | SRBA | Serbian Aviation | 1893 - 1918 | SR | TRAFFIC |
| 53 | SRBAF | Serbian Air Force and Air Defence | Ратно ваздухопловство и противваздухопловна одбрана Војске Србије | SR | TRAFFIC |
| 54 | SRBB | STRUBE | | | SCAC4 |
| 55 | SRBD | SEMI RETIRED TRUCKING CO | | | SCAC4 |
| 56 | SRBF | SENATOR SHIPPING COMPANY LIMITED | | | SCAC4 |
| 57 | SRBI | SATURN BROKERAGE INC | | | SCAC4 |
| 58 | SRBJ | SHARBER, J E OIL CO INC | | | SCAC4 |
| 59 | SRBL | S A R TRANSPORTES | | | SCAC4 |
| 60 | SRBM | STRUBLE, ROY TRUCKING INC | | | SCAC4 |
| 61 | SRBP | SIERRA RENTAL AND TRANSPORT COMPANY | | | SCAC4 |
| 62 | SRBQ | SCHNELL RACING STABLE | | | SCAC4 |
| 63 | SRBR | S R F T C BROKERS | | | SCAC4 |
| 64 | SRBS | SUNRIDGE TRANSPORTATION BROKERS | | | SCAC4 |
| 65 | SRBU | LEIDOS | | USA | BIC |
| 66 | SRBU | Leidos | | | RSRV |
| 67 | SRBU | ALBERT REBERS GMBH | | | SCAC3 |
| 68 | SRBW | SHANNON, ROBERT | | | SCAC4 |
| 69 | SRC | Searca Ltda. | Callsign: Searca, | CO | AVCODES |
| 70 | SRC | Searca | | | ICAO1 |
| 71 | SRC | Strasburg R.R. Co. | 1/1975-7/2005 | | NAKINA |
| 72 | SRC | Strasburg R.R. Co. | 1/75-7/2000 | | NRHS |
| 73 | SRC | STRASBURG RAILROAD CO. | | | PWRC |
| 74 | SRC | Strasburg Rail Road | | | RSRV |
| 75 | SRC | Sudan | | SUD | TRAFFIC |
| 76 | SRCC | SUDDATH RELOCATION SYSTEMS OF CALIF | | | SCAC4 |
| 77 | SRCD | SEPPALA, R C TRUCKING INC | | | SCAC4 |
| 78 | SRCF | SRC OPROMEX SA DE CV | | | SCAC4 |
| 79 | SRCG | SHARROCK TRUCKING INC | | | SCAC4 |
| 80 | SRCH | STARBURST COIN MACHINES INC | | | SCAC4 |
| 81 | SRCI | STAR TRUCKING INC | | | SCAC4 |
| 82 | SRCM | SERCOM | | | SCAC4 |
| 83 | SRCM | Swiss Rail Car Management GmbH | | CH | VKM |
| 84 | SRCO | SUNSET RAILWAY CO. | | | PWRC |
| 85 | SRCP | SOUTHEASTERN RECYCLING CORPORATION | | | SCAC4 |
| 86 | SRCQ | SOURCE TRANSPORT | | | SCAC4 |
| 87 | SRCR | SOLUTION RECOVERY SERVICE | | | SCAC4 |
| 88 | SRCR | Strasburg Rail Road | Real: SRC | USA | TRAFFIC |
| 89 | SRCU | NORDIC BULKERS AB | | S | BIC |
| 90 | SRCU | NORDIC BULKERS AB | | | SCAC4 |
| 91 | SRCX | Sid Richardson Carbon Co. | 1/1950-7/2005 | | NAKINA |
| 92 | SRCX | Sid Richardson Carbon Co. | 1/52-7/2000 | | NRHS |
| 93 | SRCX | SID RICHARDSON CARBON CO. | | | PWRC |
| 94 | SRCX | Sid Richardson Carbon | | | RSRV |
| 95 | SRCX | RICHARDSON, SID CARBON CO | | | SCAC3 |
| 96 | SRCX | SID RICHARDSON CARBON CO | | | SCAC4 |
| 97 | SRCY | SOURIS RIVER COLONY FARMS LTD | | | SCAC4 |
| 98 | SRD | Search And Rescue 22 | | GB | AVCODES |
| 99 | SRD | Search and Rescue 22 | | | ICAO1 |
| 100 | SRD | Scenic Rail Dining | | USA | TRAFFIC |
