Flums is a municipality in the Wahlkreis (constituency) of Sarganserland in the canton of St. Gallen in Switzerland.

It is close to a large shopping complex and also is the gateway to a large skiing resort called Flumserberg.

The municipality is located in the Sarganserland Wahlkreis. Until 2002 it was the capital of the Sargans district. In terms of area, it is the third largest municipality in the canton. Flums covers an area from the Schils valley to the border with the Canton of Glarus, part of the Flumserberge, part of the Seez valley, and the western slope of the Alvier chain. It consists of the village sections of Flums-Dorf, Grossberg, and Kleinberg.

The Gräpplang Castle (a prehistoric hilltop settlement and a ruined medieval castle), the Chapel of St. Jakob, and the catholic Church of St. Justus are listed as Swiss heritage sites of national significance.