The Siwan constituency of the Lok Sabha is encompassed in the administrative district of Siwan of the state of Bihar. The constituency is assigned the number 18 of the 40 Lok Sabha constituencies of the state of Bihar by the Election Commission of India.
The Siwan parliamentary constituency is located within the administrative district of Siwan, in the state of Bihar. The constituency is designated as number 18 out of the 40 Lok Sabha constituencies within the state of Bihar by the Election Commission of India.