The longest state highway of Jharkhand is SH-18. It is a 469 km long highway that connects Ranchi to Jamshedpur. The highway passes through the districts of Ranchi, Gumla, Simdega, Khunti, Seraikela Kharsawan, East Singhbhum, West Singhbhum, and Seraikela Kharsawan.
SH-9 is a 275 km long highway that connects Ranchi to Daltonganj. The highway passes through the districts of Ranchi, Lohardaga, Gumla, and Latehar.
SH-15 is a 245 km long highway that connects Ranchi to Hazaribagh. The highway passes through the districts of Ranchi, Ramgarh, and Hazaribagh.
SH-13 is a 230 km long highway that connects Ranchi to Bokaro. The highway passes through the districts of Ranchi, Dhanbad, and Bokaro.
Therefore, the longest state highway of Jharkhand is SH-18.