The name of the new town is based on the Raseborg Castle located in Ekenäs, or formerly in the municipality of Snappertuna.

Raseborg is a bilingual municipality with Finnish and Swedish as its official languages.

The coat of arms of Raseborg, introduced in 2009, is inspired by the area's grove biotope and the eight former municipalities that originally belonged to the united municipality, which are symbolized by white windflowers arranged in a circle.

The yellow wall crown on top of the green shield in the area therefore belongs to the history of the region and its three fortresses (including the Raseborg Castle).

It acted as the center of the Raseborg slottslän (Finnish: linnalääni) covering western Uusimaa and some parts of Finland Proper such as Kisko.