In 1980, Orfanos joined PAOK's rivals Olympiakos winning three more championships in 1981, 1982 and 1983. He played for them until the summer of 1985 when he returned to PAOK. He ended his career as a player of Apollon Kalamaria in 1988.
Orfanos was capped 8 times by the National Football Team of Greece.
After his playing career was over, Orfanos entered the administrative end of football.
Kostas Orfanos is the younger brother of politician Giorgos Orfanos.