The Băiaș is a left tributary of the river Olt in Romania. It discharges into the Olt in Copăceni. Its length is 19 km (12 mi) and its basin size is 87 km (34 sq mi).

Tributaries

The following rivers are tributaries to the river Băiaș (from source to mouth):

• Left: Grebla, Roșia, Pârâul Șasei, Pârâul Posăzii, Pârâul Starului, Șasa, Călugăreasa, Piatra Acră, Mocirlele
• Right: Râușorul, Frumușița, Dosul, Valea Stogului