Chanpatia Assembly constituency is an assembly constituency in Paschim Champaran district in the Indian state of Bihar.

Chanpatia Assembly constituency is composed of the following: Chanpatia community development block; and Chanayan Bandh, Mahana Gani, Ratanmala, Sarisawa, Barawa Semaraghat, Harpur Garawa, Dumari, Mahanwa Rampurwa, Dhokarahan, Baithania Bhanachak and Nautan Khurd gram panchayats of Majhaulia CD Block.

[1] Chanpatia Assembly constituency is part of 2.

Paschim Champaran (Lok Sabha constituency).

[1] It was earlier part of Bettiah (Lok Sabha constituency).