Echinaioi () is a former municipality in Phthiotis, Greece. Since the 2011 local government reform it is part of the municipality Stylida, of which it is a municipal unit. The municipal unit has an area of 133.052 km<sup>2</sup>. Population 3,279 (2021). The seat of the municipality was in Raches. The name of the municipality derives from the inhabitants of the ancient city of "Echinos", today's Achinos village.