Halsi is a Sub-District (Tehsil/Block/Mandal) in the Lakhisarai District of Bihar. As par Census 2011 information the sub-district code of Halsi is 01371. There are about 7 sub-districts in Lakhisarai and Halsi is one of them. Barahiya, Chanan, Lakhisarai, Pipariya, Ramgarh Chowk, Surajgarha etc. are other sub-districts in Lakhisarai.There are about 60 villages in Halsi sub-district, which you can browse from villages list.