| Boulder to Stephenville (Texas) | 666.74 mi (1,073.01 km) |
| Boulder to Sterling (Colorado) | 116.05 mi (186.77 km) |
| Boulder to Sterling (Illinois) | 820.33 mi (1,320.20 km) |
| Boulder to Sterling (Virginia) | 1,479.96 mi (2,381.77 km) |
| Boulder to Sterling Heights (Michigan) | 1,163.42 mi (1,872.34 km) |
| Boulder to Steubenville (Ohio) | 1,294.35 mi (2,083.06 km) |
| Boulder to Stevens Point (Wisconsin) | 859.10 mi (1,382.58 km) |
| Boulder to Stevenson Ranch (California) | 829.52 mi (1,334.98 km) |
| Boulder to Stillwater (Minnesota) | 720.50 mi (1,159.53 km) |
| Boulder to Stillwater (Oklahoma) | 519.47 mi (836.01 km) |
| Boulder to Stockbridge (Georgia) | 1,243.37 mi (2,001.00 km) |
| Boulder to Stockton (California) | 872.56 mi (1,404.24 km) |
| Boulder to Stone Ridge (Virginia) | 1,473.10 mi (2,370.73 km) |
| Boulder to Stonecrest (Georgia) | 1,243.12 mi (2,000.61 km) |
| Boulder to Stony Brook (New York) | 1,680.24 mi (2,704.09 km) |
