Sankhuwasabha District is one of 14 districts of Koshi Province of eastern Nepal. The district's area is 3,480 km with a population of 159,203 in …Sankhuwasabha District is one of 14 districts of Koshi Province of eastern Nepal. The district's area is 3,480 km with a population of 159,203 in 2001 and 158,742 in 2011. The administrative center is Khandbari.