Greek National Road 20 (, abbreviated as EO20) is a single carriageway road in northwestern Greece. It links the cities of Ioannina and Kozani via Konitsa and Siatista. It passes through the Ioannina, Kastoria and the Kozani regional units. Since the opening of the A2 (Egnatia Odos), it is no longer the fastest connection between Kozani and Ioannina. The section between Ioannina and Kalpaki is part of the European route E853.