Khasia and Jaintia hills (India) on the north, Habiganj and Kishoreganj districts on the south, Sylhet district on the east, Netrokona and greater Mymensingh districts on the west.

Sunamganj mahakuma (sub-division) was upgraded to a district in 1984. This district consists of 10 upazilas, 4 municipalities, 36 wards, 139 mahallas, 82 union parishads, 1711 mouzas and 2813 villages.

Bishwamvarpur Upazila, Chhatak Upazila, Derai Upazila, Dharmapasha Upazila, Dowarabazar Upazila, Jagannathpur Upazila, Jamalganj Upazila, Sullah Upazila, Sunamganj Sadar Upazila, Tahirpur Upazila