The following is a list of highways numbered S1.
China S1 Expressway (Guangdong) S1 Expressway (Henan) S1 Expressway (Hubei) S1 Expressway (Shandong) S1 Expressway (Shanghai) S1 Expressway (Sichuan) S1 Expressway (Tianjin) S1 Expressway (Tibet) S1 Expressway (Zhejiang)
Georgia S1 Highway
Poland Expressway S1 (Poland)
United States New Jersey Route S1 (former)
See also List of highways numbered 1