Sagar is a Legislative Assembly constituency located in the South 24 Parganas district of West Bengal and falls under the Mathurapur (SC) Lok Sabha constituency. Bankim Chandra Hazra of TMC is the sitting MLA in Sagar.

This constituency is composed of Sagar community development block, Fraserganj, Haripur, Mousuni, Namkhana, and Shibrampur gram panchayats of the Namkhana community development block

Here are a few details about the assembly seat in the Sagar constituency: 

Name of the assembly constituency, district: Sagar, South 24 Parganas

Lok Sabha constituency:  Mathurapur

2016 candidates: Sankhabaran Sahoo (INC), Bankim Chandra Hazra (TMC), Sarbori Mukherjee(BJP), Kamalendu Pani (SUCI (C)), Asim Kumar Mandal(CPM), Ashok Barman(LJP)

2020 candidates: NA

Sitting MLA, party: Bankim Chandra Hazra (TMC)

Winning margin in 2016: 18071

Runner up name, party: Asim Kumar Mandal (CPM)

Number of voters in 2016: 217918        

Percentage of votes polled in 2016: 89.66%

Number of women voters in 2016: 107136

Number of polling booths in 2016: 858