| Rio Grande City to Orangeburg (South Carolina) | 1,179.74 mi (1,898.60 km) |
| Rio Grande City to Orangevale (California) | 1,550.68 mi (2,495.57 km) |
| Rio Grande City to Orchards (Washington) | 1,866.14 mi (3,003.27 km) |
| Rio Grande City to Orcutt (California) | 1,407.85 mi (2,265.72 km) |
| Rio Grande City to Oregon (Ohio) | 1,370.31 mi (2,205.30 km) |
| Rio Grande City to Oregon (Wisconsin) | 1,260.56 mi (2,028.68 km) |
| Rio Grande City to Oregon City (Oregon) | 1,854.03 mi (2,983.77 km) |
| Rio Grande City to Orem (Utah) | 1,212.54 mi (1,951.39 km) |
| Rio Grande City to Orinda (California) | 1,574.16 mi (2,533.36 km) |
| Rio Grande City to Orland Park (Illinois) | 1,222.75 mi (1,967.82 km) |
| Rio Grande City to Orlando (Florida) | 1,081.01 mi (1,739.71 km) |
| Rio Grande City to Ormond Beach (Florida) | 1,100.10 mi (1,770.44 km) |
| Rio Grande City to Oro Valley (Arizona) | 841.46 mi (1,354.20 km) |
| Rio Grande City to Oroville (California) | 1,592.66 mi (2,563.13 km) |
| Rio Grande City to Oshkosh (Wisconsin) | 1,346.99 mi (2,167.77 km) |
