Frastanz is a market town in the district of Feldkirch in the westernmost Austrian state of Vorarlberg.

Frastanz is located 510 meters above sea level.

In ancient times, Frastanz was situated on a Roman Road.

Frastanz railway station is on the main west–east route connecting the Vorarlberg railway line (Vorarlbergbahn) in the directions of Bregenz and Bludenz, continuing eastward over the Arlberg Railway line to Innsbruck and beyond.

The train system is operated by the Austrian Federal Railways (ÖBB), including regional train services of Vorarlberg S-Bahn.