| Abbreviation | Definition |
|---|---|
| GSF | Georgia Southern and Florida Railway Company |
| GSIX | Gas Supply (Williams Energy Ventures) |
| GSIX | Gas Supply Incorporated |
| GSLX | George R Silcott Railway Equipment |
| GSM | Great Smokey Mountains Railway |
| GSM | Great Smoky Mountains Railroad |
| GSMR | Great Smoky Mountain Railroad |
| GSNX | Gulf States Utilities (Helm Financial Corporation) |
| GSNX | Helm Financial Corporation |
| GSOR | Indiana Hi-Rail Corporation |
| GSPU | Seacube Container Leasing |
| GSPX | Great Southern Plywood |
| GSRT | Great Southern Rail Trail |
| GSRX | Golden Spike Railroad Services |
| GSSX | Gopher State Scrap and Metal |
| GSTU | Genstar Container Corporation |
| GSW | Great Southwest Railroad |
| GSWR | Georgia Southwestern Division South Carolina Central Railroad Company |
| GSWR | South Carolina Central Railroad (Georgia Southwestern Division) |
| GSWX | G and S Supply |