Directory of Class III and regional railroads in the United States
670
Total Railroads
657
Short Lines
45
States
6
Class I
7
Class II
657
Short Line
670 railroads
| Mark | Railroad Name | Class | State(s) |
|---|---|---|---|
| SERA | Sierra Northern Railway | Short Line | |
| SMRR | Sisseton Milbank Railroad | Short Line | |
| SJRE | SJRE Railroad | Short Line | |
| SLRS | SMS Rail Service, Inc. | Short Line | |
| SBVR | South Branch Valley Railroad | Short Line | |
| SB | South Buffalo Railway | Short Line | |
| SCRF | South Carolina Central Railroad | Short Line | |
| SCXF | South Central Florida Express, Inc. | Short Line | |
| SCTR | South Central Tennessee Railroad | Short Line | |
| SCIH | South Chicago and Indiana Harbor Railway | Short Line | |
| SKOL | South Kansas and Oklahoma Railroad | Short Line | |
| SLAL | South Plains Lamesa Railroad | Short Line | |
| SPOR | South Point and Ohio Railroad | Short Line | |
| SERC | Southern Electric Railroad Company | Short Line | |
| SRNJ | Southern Railroad of New Jersey | Short Line | |
| SSC | Southern Switching Company | Short Line | |
| SWG | Southwest Gulf Railroad | Short Line | |
| SWP | Southwest Pennsylvania Railroad | Short Line | |
| SW | Southwestern Railroad | Short Line | |
| SSPR | Spokane, Spangle & Palouse Railway | Short Line | |
| SCS | Squaw Creek Southern Railroad | Short Line | |
| SCXY | St. Croix Valley Railroad | Short Line | |
| SLR | St. Lawrence and Atlantic Railroad | Short Line | |
| STMA | St. Maries River Railroad | Short Line | |
| SM | St. Marys Railroad | Short Line | |
| SMW | St. Marys Railway West | Short Line | |
| SPPN | St. Paul and Pacific Northwest Railroad | Short Line | |
| SPPR | St. Paul and Pacific Railroad | Short Line | |
| SLWC | Stillwater Central Railroad | Short Line | |
| STE | Stockton Terminal and Eastern Railroad | Short Line | |
| SBRR | Stourbridge Railroad | Short Line | |
| SRC | Strasburg Rail Road | Short Line | |
| SRRR | Swan Ranch Railroad | Short Line | |
| TMBL | Tacoma Rail | Short Line | |
| TZPR | Tazewell and Peoria Railroad | Short Line | |
| TC | Temple and Central Texas Railway | Short Line | |
| TSRR | Tennessee Southern Railroad | Short Line | |
| TKEN | Tennken Railroad | Short Line | |
| TRRA | Terminal Railroad Association of St. Louis | Short Line | |
| TASD | Terminal Railway Alabama State Docks | Short Line | |
| TXN | Texas & New Mexico Railroad | Short Line | |
| TESR | Texas and Eastern Railroad | Short Line | |
| TN | Texas and Northern Railway | Short Line | |
| TXOR | Texas and Oklahoma Railroad | Short Line | |
| TCB | Texas Central Business Lines Corporation | Short Line | |
| TCT | Texas City Terminal Railway | Short Line | |
| TCBR | Texas Coastal Bend Railroad | Short Line | |
| TXNW | Texas North Western Railway | Short Line | |
| TNER | Texas Northeastern Railroad | Short Line | |
| TXPF | Texas Pacifico Transportation | Short Line |
Source: Wikipedia "List of United States railroads". 670 railroads indexed.