| Boston to Santarem | 1,034.35 mi (1,664.62 km) |
| Boston to Santiago do Cacem | 1,113.72 mi (1,792.36 km) |
| Boston to Santo Andre | 1,112.44 mi (1,790.31 km) |
| Boston to Santo Tirso | 895.41 mi (1,441.02 km) |
| Boston to Sao Bras de Alportel | 1,157.02 mi (1,862.05 km) |
| Boston to Sao Felix da Marinha | 917.62 mi (1,476.76 km) |
| Boston to Sao Joao da Madeira | 923.62 mi (1,486.42 km) |
| Boston to Sao Joao de Ver | 921.25 mi (1,482.60 km) |
| Boston to Sao Mamede de Infesta | 906.60 mi (1,459.04 km) |
| Boston to Sao Pedro do Sul | 924.80 mi (1,488.32 km) |
| Boston to Satao | 919.64 mi (1,480.01 km) |
| Boston to Seia | 939.25 mi (1,511.58 km) |
| Boston to Senhora da Hora | 908.54 mi (1,462.16 km) |
| Boston to Serpa | 1,099.95 mi (1,770.20 km) |
| Boston to Serta | 986.82 mi (1,588.14 km) |
