According to the United States Census Bureau, the township has a total area of 46.6 square miles (120.7 km²), of which, 46.5 square miles (120.4 km²) of it is land and 0.1 square miles (0.3 km²) of it (0.21%) is water.
White Deer Township is bordered by Lycoming County and Gregg Township to the north, the West Branch Susquehanna River to the east over which lies Northumberland County, Kelly and Buffalo Townships to the south and West Buffalo Township to the west.