| Rio Grande City to Somersworth (New Hampshire) | 1,951.64 mi (3,140.86 km) |
| Rio Grande City to Somerton (Arizona) | 1,045.65 mi (1,682.80 km) |
| Rio Grande City to Somerville (Massachusetts) | 1,914.88 mi (3,081.71 km) |
| Rio Grande City to Somerville (New Jersey) | 1,695.94 mi (2,729.36 km) |
| Rio Grande City to Sonoma (California) | 1,599.52 mi (2,574.18 km) |
| Rio Grande City to Soquel (California) | 1,538.98 mi (2,476.74 km) |
| Rio Grande City to South Bend (Indiana) | 1,274.98 mi (2,051.87 km) |
| Rio Grande City to South Bradenton (Florida) | 1,002.50 mi (1,613.37 km) |
| Rio Grande City to South Burlington (Vermont) | 1,892.92 mi (3,046.36 km) |
| Rio Grande City to South Charleston (West Virginia) | 1,292.14 mi (2,079.49 km) |
| Rio Grande City to South Daytona (Florida) | 1,104.88 mi (1,778.14 km) |
| Rio Grande City to South El Monte (California) | 1,261.52 mi (2,030.22 km) |
| Rio Grande City to South Elgin (Illinois) | 1,232.18 mi (1,983.01 km) |
| Rio Grande City to South Euclid (Ohio) | 1,435.82 mi (2,310.73 km) |
| Rio Grande City to South Farmingdale (New York) | 1,754.81 mi (2,824.09 km) |
