Iolcos (; also rendered Iolkos or Iolcus ; Greek: Ιωλκός) is an ancient city, a modern village and a former municipality in Magnesia, Thessaly, Greece. Since the 2011 local government reform it is part of the municipality Volos, of which it is a municipal unit. It is located in central Magnesia, north of the Pagasitic Gulf. Its land area is 1.981 km². The municipal unit is divided into three communities, Agios Onoufrios (pop. 475), Anakasia (pop. 1012) and Ano Volos (pop. 651), with a total population of 2,138 (2011 census). The seat of the former municipality was the village of Ano Volos.