Borriol is a town and municipality in the province of Castellón, within the Valencian Community of eastern Spain. It lies in the comarca of Plana Alta, a short distance inland from the provincial capital, Castellón de la Plana.
The municipality sits at the foot of the Serra de Borriol, a small coastal mountain range that rises just to the west of the town. This setting gives Borriol a landscape of low hills and rocky slopes, distinct from the flatter coastal plain that stretches toward the Mediterranean.
Borriol is one of several small inland settlements that make up the Plana Alta, and it retains the character of a traditional Valencian town while functioning as a residential municipality within the wider Castellón metropolitan area. The town is connected to Castellón de la Plana and neighbouring municipalities by local roads.