| Name | What | Region | Country | Lat | Long | Elev ft. | Pop est |
|---|---|---|---|---|---|---|---|
| Rio Sal Arriba | city | Oaxaca | Mexico | 15.90 | -96.31 | 1174 | 4669 |
| Rio Salado | city | Nuevo Leon | Mexico | 26.89 | -99.85 | 830 | 104 |
| Rio Salado | city | Tamaulipas | Mexico | 26.79 | -99.43 | 318 | 126 |
| Rio Salinas | city | Oaxaca | Mexico | 16.68 | -97.12 | 6709 | 520 |
| Rio San Jose | city | Oaxaca | Mexico | 16.17 | -96.40 | 9228 | 3295 |
| Rio San Juan | city | Oaxaca | Mexico | 16.09 | -96.65 | 2509 | 3484 |
| Rio San Juan Numi | city | Oaxaca | Mexico | 17.40 | -97.68 | 6824 | 1733 |
| Rio San Miguel | city | Oaxaca | Mexico | 16.73 | -98.00 | 1669 | 3810 |
| Rio Santa Cruz | city | Oaxaca | Mexico | 15.95 | -96.68 | 2509 | 4395 |
| Rio Santa Maria | city | Chihuahua | Mexico | 28.14 | -108.53 | 2562 | 298 |
| Rio Santa Rita | city | Chihuahua | Mexico | 26.80 | -106.60 | 7549 | 298 |
| Rio Santiago | city | Guerrero | Mexico | 17.25 | -100.32 | 2509 | 5066 |
| Rio Santiago | city | Oaxaca | Mexico | 16.67 | -97.26 | 6059 | 2972 |
| Rio Saucito | city | Sonora | Mexico | 29.22 | -110.87 | 849 | 69142 |
| Rio Seco | city | Oaxaca | Mexico | 17.25 | -97.09 | 6889 | 3984 |
| Rio Seco Norte Diez | city | Tabasco | Mexico | 18.09 | -93.39 | 36 | 14724 |
| Rio Seco Primera Seccion | city | Tabasco | Mexico | 18.11 | -93.32 | 29 | 17450 |
| Rio Seco Segunda Seccion | city | Tabasco | Mexico | 18.06 | -93.38 | 42 | 15413 |
| Rio Seco Segunda Seccion "A" | city | Tabasco | Mexico | 18.05 | -93.38 | 45 | 16473 |
| Rio Seco Segunda Seccion "B" | city | Tabasco | Mexico | 18.06 | -93.38 | 42 | 15413 |
| Rio Seco Segunda Seccion "C" | city | Tabasco | Mexico | 18.08 | -93.37 | 42 | 16234 |
| Rio Seco y Montana Segunda Seccion | city | Tabasco | Mexico | 17.97 | -93.37 | 72 | 22026 |
| Rio Seco y Puente de Doria | city | Hidalgo | Mexico | 20.21 | -98.51 | 6919 | 5183 |