Isabela City is a 3rd-class component city in the Philippines, located in Mindanao. It is geographically part of Basilan, which is part of the Bangsamoro Autonomous Region in Muslim Mindanao (BARMM). However, it voted against joining the new Bangsamoro region in the 2019 plebiscite. For this reason, it is administratively part of Zamboanga Peninsula.