| Tamasio | |
| Name Local: | Ταμάσιο |
| Type: | municipal unit |
| Periph: | Thessaly |
| Periphunit: | Karditsa |
| Population: | 2421 |
| Population As Of: | 2021 |
| Area: | 163.5 |
| Coordinates: | 39.2°N 30°W |
| Licence: | ΚΑ |
Tamasio (el|Ταμάσιο) is a former municipality in the Karditsa regional unit, Thessaly, Greece. Since the 2011 local government reform it is part of the municipality Sofades, of which it is a municipal unit.[1] The municipal unit has an area of 163.504 km2.[2] Population 2,421 (2021). The seat of the municipality was in Leontari. The municipality was named after Mount Tamassion (Tamasion was also the old name of the village of Anavra).