Calfreisen (Romansh: ) is a former municipality in the district of Plessur in the canton of Graubünden in Switzerland . On 1 January 2013 the former municipalities of Calfreisen, Castiel, Langwies , Lüen , Molinis , Peist and St. Peter-Pagig merged into the municipality of Arosa .

Calfreisen is first mentioned in 1156 as Caureisene.

Before the merger, Calfreisen had a total area of 5.2 km2 (2.0 sq mi). Of this area, 49.5% is used for agricultural purposes, while 30% is forested.