It consists of the town of Uusikaupunki and its surrounding municipalities of Kustavi, Laitila, Mietoinen, Mynämäki, Pyhäranta, Taivassalo and Vehmaa.

The composition of the area is disputable, as communities within it have been and are merged into each other, even into ones that are not seen to belong into Vakka-Suomi.

For example, Kalanti and Lokalahti are no longer their own municipalities, but a part of Uusikaupunki.

A vakka is a commonly a lightweight container made out of wood, generally carryable by two hands.

It has an easily fitting lid that has a locking mechanism and is commonly without hinges.