| Duncan to Stephenville (Texas) | 161.64 mi (260.14 km) |
| Duncan to Sterling (Colorado) | 509.43 mi (819.85 km) |
| Duncan to Sterling (Illinois) | 671.04 mi (1,079.94 km) |
| Duncan to Sterling (Virginia) | 1,173.77 mi (1,889.00 km) |
| Duncan to Sterling Heights (Michigan) | 975.37 mi (1,569.70 km) |
| Duncan to Steubenville (Ohio) | 1,026.91 mi (1,652.66 km) |
| Duncan to Stevens Point (Wisconsin) | 820.43 mi (1,320.35 km) |
| Duncan to Stevenson Ranch (California) | 1,175.28 mi (1,891.43 km) |
| Duncan to Stillwater (Minnesota) | 774.81 mi (1,246.94 km) |
| Duncan to Stillwater (Oklahoma) | 119.85 mi (192.87 km) |
| Duncan to Stockbridge (Georgia) | 786.51 mi (1,265.76 km) |
| Duncan to Stockton (California) | 1,320.91 mi (2,125.79 km) |
| Duncan to Stone Ridge (Virginia) | 1,164.97 mi (1,874.84 km) |
| Duncan to Stonecrest (Georgia) | 790.13 mi (1,271.60 km) |
| Duncan to Stony Brook (New York) | 1,418.92 mi (2,283.53 km) |
