Situated within the valley of the Möll river, a tributary to the Drava, Reißeck is located about northwest of the district capital Spittal an der Drau. The present-day municipality established in 1973 consists of the four cadastral communities Kolbnitz, Zandlach, Penk, and Teuchl. It was named after the Reißeck massif (2,965m/9,727 ft) in the north, part of the Ankogel Group of the Hohe Tauern mountain range. South of the Möll Valley rises the Kreuzeck Group.