Kasba is a Sub-District (Tehsil/Block/Mandal) in the Purnia District of Bihar. As par Census 2011 information the sub-district code of Kasba is 01135. There are about 14 sub-districts in Purnia and Kasba is one of them. Amour, Baisa, Baisi, Banmankhi, Barhara, Bhawanipur, Dagarua, Dhamdaha, Jalalgarh, Krityanand Nagar, Purnia East, Rupauli, Srinagar etc. are other sub-districts in Purnia.There are about 56 villages in Kasba sub-district, which you can browse from villages list.