Biliran became a regular province on May 11, 1992 after a plebiscite was conducted in accordance with R.A. 7160. The island province, which was formerly a sub-province of Leyte, belongs to the Eastern Visayas region (Region 8). It is bounded on the north by the Visayas Sea, on the south by the Carigara Bay, on the east by the Samar Sea, and on the west by the Strait of Biliran.
The province of Biliran consists of 8 municipalities and 132 barangays. It is a lone congressional district. The seat of government is in Naval, the capital town.
The main island has slightly flat to rolling and rough terrain. It has narrow coastal areas or lowlands with mountainous interiors except for the municipalities of Naval and Caibiran that have wider plains and rolling terrain extending about 7 km from the coast. Mountain ranges occupy the major portion of the island municipality of Maripipi.