 Born in Agios Pavlos, Thessaloniki, Koudas began playing football for PAOK where he made his first-team debut in December 1963, aged 17.Koudas, nicknamed "Alexander the Great", spent his entire football career with PAOK, making 504 appearances in the Alpha Ethniki from 1963 to 1984, and 607 appearances in all competitions (PAOK all-time records).Koudas won two out of nine Greek Cup finals he appeared in and in the 1972 Cup final, he scored both goals as PAOK defeated Panathinaikos 2–1 and earned their first domestic title in club's history.