“Macedonia” airport of Thessaloniki is an international airport located 13km south of the Thessaloniki city centre in Thermi. It is country’s third largest airport (after Athens’s and Heraklion’s). It is the main airport of northern part of the country.
The airport is served on a 24-hour basis by OASTH (Thessaloniki Urban Transport Organization), with buses providing direct access to the centre of the city. The journey takes about 30-40 minutes.
Find out more: http://oasth.gr/#en/airport-macedonia/
There is a taxi rank outside the Arrivals hall. One-way ride costs around 20€.
You can rent a car directly at the airport in one of the offices of rental companies like Hertz Avis, Europcar, Sixt and Budget. The car rental offices are located at the Arrivals Level.