The Vrbas (Serbian Cyrillic: Врбас, pronounced [ʋr̩̂ba(ː)s]) is a major river with a length of 250 kilometres (160 mi), in western Bosnia and Herzegovina.

[7] The word vrba means 'willow' in Serbo-Croatian, and a number of weeping willow trees adorn the river banks in Banja Luka.

Middle Vrbas mostly comprises a canyon section, with steep slopes and narrow passages, between Jajce and Banja Luka.

Maximum rainfall occurs in the southern parts of the Vrbas basin in the late autumn and winter months, with minimum quantities in summer, whereas the northern parts of the basin receive the largest quantities of rain during the summer months (June–July), with the maximum in November and December.

The Vrbas basin is known for an abundant ichthyofauna, rich in species, and recreational and fly fishing are very popular on entire cours of the river.

Of all the Vrbas tributaries only the river Vrbanja, and possibly Ugar, also retain healthy population of this endemic fish.