Akhaura, Brahmanbaria Sadar and Nabinagar upazilas on the north, Brahmanpara upazila on the south, Tripura State of India on the east, Nabinagar, Muradnagar and Brahmanpara upazilas on the west.

Kasba thana was established in 1908 and was turned into an upazila in 1983. The upazila consists of 10 union parishads, 160 mouzas and 236 villages.

Kasba Upazila is located in Brahmanbaria District. Upazilla(s)/Thana(s) in Brahmanbaria are Akhaura Upazila, Bancharampur Upazila, Brahmanbaria Sadar Upazila, Kasba Upazila, Nabinagar Upazila, Nasirnagar Upazila, Sarail Upazila.

Sree Sree Anandamoye Ashram at Kheora (seventeenth century), Bara Mosque at Kuti (eighteenth century).