List of reporting marks: S

S

 * SA  - Savannah and Atlanta Railroad; Central of Georgia Railroad
 * SAL - Seaboard Air Line Railway; Seaboard System Railroad; CSX Transportation
 * SAMX - Cargill, Inc. (Seaboard Allied Milling Department)
 * SAN - Sandersville Railroad
 * SANX - San Angelo Tank Car Line
 * SAPT - Savannah Port Terminal Railroad
 * SATX - City Public Service Board of San Antonio
 * SAUX - Sauvage Gas Company
 * SAWX - Sawco, Inc.
 * SAZX - Saz Transportation Corporation
 * SB  - South Buffalo Railway
 * SBC - Ferrocarril Sonora Baja California
 * SBD - Seaboard System Railroad; CSX Transportation
 * SBGX - Industry Financial Corporation
 * SBIX - Standard Brands, Inc.
 * SBK - South Brooklyn Railway
 * SBLN - Sterling Belt Line Railway
 * SBLX - Sunbelt/Chlor/Alkali Partnership
 * SBM - St. Louis, Brownsville and Mexico
 * SBVR - South Branch Valley Railroad
 * SC  - Sumter and Choctaw Railway
 * SCAX - Southern California Regional Rail Authority (Metrolink)
 * SCBG - Santa Cruz, Big Trees and Pacific Railway


 * SCCX - Shell Oil Company
 * SCEX - Southern California Edison
 * SCFE - South Central Florida Railroad
 * SCFS - Straits Car Ferry Service Corporation
 * SCGX - Schuler Grain Company; Eades Commodities
 * SCHX - Stauffer Chemical Company
 * SCJX - Gulf Oil Products Company; Chevron Phillips Chemical Company
 * SCL - Seaboard Coast Line Railroad; Seaboard System Railroad; CSX Transportation
 * SCLX - Spielman & Caddell Leasing
 * SCM - Strouds Creek and Muddlety Railroad
 * SCMX - Shell Oil Company
 * SCOX - Scoular Bishop Grain Company
 * SCPX - Shell Oil Company
 * SCR - SCR
 * SCRW - Seaway Commercial Railway
 * SCST - Seaboard Transportation Company (subsidiary of Seaboard Coast Line Railroad)
 * SCT - Sioux City Terminal Railway
 * SCTR - South Central Tennessee Railroad
 * SCWX - South Carolina Public Service Authority
 * SCXF - South Central Florida Express, Inc.
 * SCXY - St. Croix Valley Railroad
 * SCYX - Farmers Cooperative Association of York, Nebraska
 * SDA - San Diego and Arizona Railway
 * SDAE - San Diego and Arizona Eastern Railway
 * SDCX - AMAX Chemical Corporation
 * SDER - San Diego Electric Railway
 * SDEX - Swindell-Dressler Energy Supply Company
 * SDIV - San Diego and Imperial Valley Railroad (expired)
 * SDIY - San Diego and Imperial Valley Railroad
 * SDNX - North County Transit District
 * SDPX - South Dakota Soybeen Processors
 * SDRX - Sounder commuter rail
 * SE  - Ferrocarriles Unidos del Sureste
 * SECX - South-East Coal Company
 * SEIX - Seimax Gas Corporation
 * SEMX - Seminole Electric Cooperative
 * SEPA - SEPTA
 * SEPX - Southwestern Electric Power Company
 * SERA - Sierra Railroad
 * SERX - ACF Industries (Shippers Car Line Division)
 * SFIX - System Fuels, Inc.
 * SFLC - Atchison, Topeka and Santa Fe Railway; BNSF Railway
 * SFLR - Shore Fast Line Railroad
 * SFPP - Spruce Fall Power and Paper
 * SFQ - Atchison, Topeka and Santa Fe Railway; BNSF Railway End Of Train Devices
 * SFRB - Atchison, Topeka and Santa Fe Railway (Santa Fe Refrigerated Despatch)
 * SFRC - Atchison, Topeka and Santa Fe Railway (Santa Fe Refrigerated Despatch)
 * SFRD - Atchison, Topeka and Santa Fe Railway (Santa Fe Refrigerated Despatch)
 * SFRE - Atchison, Topeka and Santa Fe Railway (Santa Fe Refrigerated Despatch)
 * SFRP - Atchison, Topeka and Santa Fe Railway (Santa Fe Refrigerated Despatch)
 * SFSR - Santa Fe Southern Railway
 * SFSX - San Francisco Transportation Services Company
 * SFTX - Continental Tank Car Corporation
 * SGAX - SGA Leasing Company
 * SGCX - Sungas Corporation of Florida
 * SGIX - LPG Transportation, Inc.
 * SGLR - Seminole Gulf Railway
 * SH  - Steelton and Highspire Railroad
 * SHPX - American Industrial Transport, formerly ACF Leasing/Shippers Car Line Division
 * SHQX - American Industrial Transport
 * SHRX - Kansas City Railroad Museum
 * SI  - Spokane International Railroad; Union Pacific Railroad
 * SIGX - Southern Indiana Gas and Electric Company
 * SIMX - Sierra Bag Company
 * SIND - Southern Indiana Railway
 * SIRC - Staten Island Railway
 * SIRR - Southern Industrial Railroad
 * SIRX - Southern Illinois Railcar Corporation
 * SJFX - Western Fuels & Asphalt Supply, Inc.; GLNX Corporation
 * SJMX - St. Joe Minerals Corporation
 * SJRT - St. Johns River Terminal
 * SJT - St. Joseph Terminal Railroad
 * SJVR - San Joaquin Valley Railroad
 * SKCX - ARCO Chemical Company
 * SKNX - Saskatchewan Grain Car Corporation
 * SKOL - South Kansas and Oklahoma Railroad
 * SKPX - Saskatchewan Grain Car Corporation
 * SKSX - Safety-Kleen Systems, Inc.
 * SKTX - Ski Train
 * SL  - Salt Lake City Southern Railroad
 * SLAW - St. Lawrence Railroad
 * SLAX - St. Lawrence Starch Company, Ltd.
 * SLC - San Luis Central Railroad
 * SLGG - Sidney and Lowe Railroad
 * SLGW - Salt Lake, Garfield and Western Railway
 * SLH - Sugarloaf and Hazelton Railroad
 * SLOX - Selox, Inc.
 * SLR - St. Lawrence and Atlantic Railroad
 * SLRG - San Luis and Rio Grande Railroad
 * SLRX - St. Louis Refrigerator Car Company
 * SLSF - St. Louis - San Francisco Railway (Frisco); Burlington Northern Railroad
 * SLWC - Stillwater Central Railroad
 * SLTX - Slade Transport, Inc.
 * SM  - St. Mary's Railroad
 * SMA - San Manuel Arizona Railroad
 * SMCX - San Miguel Electric Cooperative
 * SMEX - South Mississippi Electric Power Association
 * SMMX - St. Mary's Cement Company
 * SMPX - Stone Mountain Scenic Railroad
 * SMRR - Sisseton Milbank Railroad
 * SMNX - Solvay Minerals, Inc.
 * SMRX - Southeastern Railway Museum
 * SMV - Santa Maria Valley Railroad
 * SN  - Sacramento Northern Railway
 * SNBL - Sioux City and New Orleans Barge Line
 * SNCT - Seattle and North Coast Railroad
 * SNFX - IND/AG Chemicals, Inc.
 * SNHX - IND/AG Chemicals, Inc.
 * SNJX - New Jersey Transit RiverLINE work train
 * SOEX - Shell Oil Company
 * SOGX - Diamond Shamrock Chemicals Company
 * SOIX - Sand Seed Service, Inc.
 * SOLX - Solano Rail Car Company
 * SOM - Somerset Railroad
 * SOO - Soo Line Railroad; Canadian Pacific Railway
 * SOPR - South Pierce Railroad
 * SOR - Southern Ontario Railway
 * SOU - Southern Railway; Norfolk Southern Railway
 * SP  - Southern Pacific Railroad; Union Pacific Railroad
 * SPAX - SEPTA
 * SPCX - SPC Rail Group LLC
 * SPEG - Spencerville and Elgin Railroad
 * SPFE - Pacific Fruit Express; Southern Pacific Railroad; Union Pacific Railroad
 * SPGX - Suburban Propane
 * SPMW - Southern Pacific Railroad; Union Pacific Railroad (maintenance of Way)
 * SPQ - Southern Pacific Railroad; Union Pacific Railroad End Of Train Devices
 * SPS - Spokane, Portland and Seattle Railway; Burlington Northern Railroad
 * SPSX - Progress Rail Services
 * SPUD - St. Paul Union Depot Company
 * SQVR - Sequatchie Valley Railroad
 * SRAX - Southern Rail Associates, Inc.
 * SRC - Strasburg Railroad
 * SRCX - Sid Richardson Carbon Company
 * SRIX - Southern Region Industrial Realty, Inc.; Southwest Rail Industries, Inc.
 * SRL - Swift Refrigerator Lines (expired)
 * SRLX - General American Transportation Corporation
 * SRN - Sabine River and Northern Railroad
 * SROX - United States Department of Energy (Savannah River Operations Office)
 * SRPX - Salt River Project Agricultural Improvement and Power District
 * SRRX - Star Railroad Equipment
 * SRY - Southern Railway of British Columbia
 * SS  - Sand Springs Railway
 * SSAM - Sault Ste. Marie Bridge Company (subsidiary of Wisconsin Central)
 * SSDK - Savannah State Docks Railroad
 * SSGX - McMaster Grain Company
 * SSH - South Shore Railroad
 * SSEX - Schnitzer Steel Industries
 * SSIX - Itel Corporation
 * SSW - St. Louis Southwestern Railway (Cotton Belt); Southern Pacific Railroad; Union Pacific Railroad
 * ST  - Springfield Terminal Railway; Boston and Maine Railroad; Pan Am Railways
 * STAX - Stauffer Chemical Company; OCI Chemical Corporation
 * STCX - Sterling China Company
 * STE - Stockton Terminal and Eastern Railroad
 * STER - St. Thomas and Eastern Railway
 * STEX - Sterling Chemicals, Inc.
 * STLE - St. Louis & Evansville Railroad Co.
 * STLX - A. E. Staley
 * STMA - St. Maries River Railroad
 * STMX - A. E. Staley
 * STOX - ACF Industries
 * STRC - Stuart Chemical Transportation
 * STRT - Stewartstown Railroad
 * STRX - St. Regis Paper Company
 * STSX - A. E. Staley
 * STTX - Trailer Train Company
 * STWX - Struthers Wells Corporation
 * SULX - Sultran
 * SUN - Sunset Railway
 * SUNX - Sun Refining and Marketing Company
 * SUR - State University Railroad
 * SVGX - Savage services
 * SVI - Southern Railway of Vancouver Island, E and N Railway
 * SVIL - Saltville Railroad
 * SW  - Southwestern Railroad
 * SWCX - Estech, Inc.
 * SWFX - Southwest Forest Industries, Inc.
 * SWGX - Southwest Georgia Railroad Excursion Authority/SAM Shortline Excursion Train
 * SWIX - Stonewall Industries LLC
 * SWLX - Essel Corporation
 * SWRX - Richmond Rail Equipment Leasing Company
 * SWYX - Stauffer Chemical Company of Wyoming