Avressieux (French pronunciation: [avʁɛsjø]; Arpitan: Avarcheû) is a commune in the Savoie department in the Auvergne-Rhône-Alpes region in south-eastern France.

As with many polysyllabic Arpitan toponyms or anthroponyms, the final -x marks oxytonic stress (on the last syllable), whereas the final -z indicates paroxytonic stress (on the penultimate syllable) and should not be pronounced, although in French it is often mispronounced due to hypercorrection.