| Duncan to Scottsboro (Alabama) | 674.93 mi (1,086.20 km) |
| Duncan to Scottsdale (Arizona) | 799.17 mi (1,286.14 km) |
| Duncan to Scranton (Pennsylvania) | 1,297.07 mi (2,087.44 km) |
| Duncan to Seabrook (Maryland) | 1,202.98 mi (1,936.01 km) |
| Duncan to Seabrook (Texas) | 382.72 mi (615.92 km) |
| Duncan to Seaford (New York) | 1,397.31 mi (2,248.75 km) |
| Duncan to Seagoville (Texas) | 152.58 mi (245.56 km) |
| Duncan to Seal Beach (California) | 1,151.57 mi (1,853.28 km) |
| Duncan to Searcy (Arkansas) | 353.87 mi (569.50 km) |
| Duncan to Seaside (California) | 1,347.10 mi (2,167.94 km) |
| Duncan to SeaTac (Washington) | 1,542.11 mi (2,481.79 km) |
| Duncan to Seattle (Washington) | 1,548.66 mi (2,492.33 km) |
| Duncan to Sebastian (Florida) | 1,129.79 mi (1,818.22 km) |
| Duncan to Sebring (Florida) | 1,088.60 mi (1,751.93 km) |
| Duncan to Secaucus (New Jersey) | 1,369.13 mi (2,203.40 km) |
