Plentzia (Spanish: Plencia) is a town and municipality located in the province of Biscay, in the autonomous community of the Basque Country.

The beach is very popular as it is clean and the sea is calm due to the shelter of the bay and the town has many amenities for visitors.

The town also has an indoor municipal Jai Alai Fronton where the traditional Basque sport of pelota is played and competitive matches can often be seen.

The origins of Plentzia goes back to the beginning of the 13th century, when the Lord of Vizcaya Lope Díaz II of Haro define the maritime term of the district of Gorliz, focused on whale hunting.

It stood in the area coastal Gaminiz, belonging to the community of Gorliz, which would separate the whole which would constitute the town of Plentzia.