Kasthamahal is a village in Bishnupur I tehsil in district of South Twenty Four Parganas, West Bengal, India. As per the data provided by Census of India in 2011, total population of Kasthamahal was 5,156 which includes 2,716 males and 2,440 females. Kasthamahal covers 318.8 ha area. Pincode of Kasthamahal is 743503.