| Helena to Carrollwood (Florida) | 2,045.38 mi (3,291.73 km) |
| Helena to Carson (California) | 940.18 mi (1,513.08 km) |
| Helena to Carson City (Nevada) | 645.64 mi (1,039.06 km) |
| Helena to Carteret (New Jersey) | 1,916.88 mi (3,084.92 km) |
| Helena to Cartersville (Georgia) | 1,657.79 mi (2,667.96 km) |
| Helena to Carthage (Missouri) | 1,116.09 mi (1,796.17 km) |
| Helena to Cary (Illinois) | 1,206.72 mi (1,942.03 km) |
| Helena to Cary (North Carolina) | 1,863.46 mi (2,998.95 km) |
| Helena to Casa de Oro-Mount Helix (California) | 990.77 mi (1,594.49 km) |
| Helena to Casa Grande (Arizona) | 945.96 mi (1,522.37 km) |
| Helena to Casas Adobes (Arizona) | 986.32 mi (1,587.32 km) |
| Helena to Cascades (Virginia) | 1,814.59 mi (2,920.30 km) |
| Helena to Casper (Wyoming) | 381.37 mi (613.76 km) |
| Helena to Casselberry (Florida) | 2,065.71 mi (3,324.43 km) |
| Helena to Castaic (California) | 905.35 mi (1,457.03 km) |
