| Rank | Country | Railways |
46 | Slovakia | total: 3,662 km broad gauge: 100 km 1.520-m gauge standard gauge: 3,512 km 1.435-m gauge (1,588 km electrified) narrow gauge: 50 km (1.000-m or 0.750-m gauge) (2006) |
84 | Slovenia | total: 1,229 km standard gauge: 1,229 km 1.435-m gauge (504 km electrified) (2006) |
| Solomon Islands | void |
| Somalia | void |
14 | South Africa | total: 20,872 km narrow gauge: 20,436 km 1.065-m gauge (8,931 km electrified); 436 km 0.610-m gauge (2006) |
| South Georgia and the South Sandwich Islands | void |
| Southern Ocean | void |
18 | Spain | total: 14,974 km broad gauge: 11,919 km 1.668-m gauge (6,950 km electrified) standard gauge: 1,099 km 1.435-m gauge (1,054 km electrified) narrow gauge: 1,928 km 1.000-m gauge (815 km electrified); 28 km 0.914-m gauge (28 km electrified) (2006) |
| Spratly Islands | void |
81 | Sri Lanka | total: 1,449 km broad gauge: 1,449 km 1.676-m gauge (2006) |
30 | Sudan | total: 5,978 km narrow gauge: 4,578 km 1.067-m gauge; 1,400 km 0.600-m gauge for cotton plantations (2006) |
| Suriname | void |
| Svalbard | void |
124 | Swaziland | total: 301 km narrow gauge: 301 km 1.067-m gauge (2006) |
20 | Sweden | total: 11,528 km standard gauge: 11,528 km 1.435-m gauge (7,527 km electrified) (2006) |
36 | Switzerland | total: 4,839 km standard gauge: 3,561 km 1.435-m gauge (3,195 km electrified) narrow gauge: 1,268 km 1.000-m gauge (1,274 km electrified); 10 km 0.800-m gauge (10 km electrified) (2006) |
62 | Syria | total: 2,711 km standard gauge: 2,460 km 1.435-m gauge narrow gauge: 251 km 1.050-m gauge (2006) |
80 | Taiwan | total: 1,588 km standard gauge: 345 km 1.435-m gauge narrow gauge: 1,093 km 1.067-m gauge note: 150 km .762-m gauge (belonging primarily to Taiwan Sugar Corporation and Taiwan Forestry Bureau; some to other entities) (2007) |
117 | Tajikistan | total: 482 km broad gauge: 482 km 1.520-m gauge (2006) |
45 | Tanzania | total: 3,690 km narrow gauge: 969 km 1.067-m gauge; 2,721 km 1.000-m gauge (2006) |
41 | Thailand | total: 4,071 km narrow gauge: 4,071 km 1.000-m gauge (2006) |
| Timor-Leste | void |
112 | Togo | total: 568 km narrow gauge: 568 km 1.000-m gauge (2006) |