Nangalkot upazila on the north, Noakhali Sadarand Companiganj (Noakhali) upazilas on the south, Daganbhuiyan upazila on the east and Begumganj and Laksham upazilas on the west.

Senbagh thana was turned into an upazila in 1983. It consists of 9 union parishads, 99 mouzas and 111 villages.

Senbagh Upazila is located in Noakhali District. Upazilla(s)/Thana(s) in Noakhali are Begumganj Upazila, Chatkhil Upazila, Companiganj Upazila, Hatiya Upazila, Noakhali Sadar Upazila, Senbagh Upazila.