Harnatanr is a village in Sidhaw tehsil in district of Pashchim Champaran, Bihar, India. As per the data provided by Census of India in 2011, total population of Harnatanr was 3,967 which includes 2,065 males and 1,902 females. Harnatanr covers 170 ha area. Pincode of Harnatanr is 845105.