Thermi is a Southeastern suburb and a municipality in the Thessaloniki regional unit, Macedonia, Greece. Its population was 55,358 at the 2…Thermi is a Southeastern suburb and a municipality in the Thessaloniki regional unit, Macedonia, Greece. Its population was 55,358 at the 2021 census. It is located over the site of ancient Therma. The municipality Thermi has an area of 382.106 km², the municipal unit Thermi has an area of 100.943 km², and the community Thermi has an area of 55.90 km².