Arza Nagar is a village in Ramgarhwa tehsil in district of Purba Champaran, Bihar, India. As per the data provided by Census of India in 2011, total population of Arza Nagar was 1,428 which includes 765 males and 663 females. Arza Nagar covers 109.7 ha area. Pincode of Arza Nagar is 845433.