Clubs
Nightclubs can be found in many destinations in Greece. They open from around midnight and stay open till 6 or 7 a.m. Many of these Greek island clubs, particularly in Mykonos, Paros, Ios, Crete, Rhodes, Kos.
Bars and Pubs
Bars in Greece stay open until late at night and each bar plays a different kind of music, from Greek and international pop to alternative rock, jazz, Latin and much more. Such bars are found in all Greek islands. they usually stay open till 2 or 3 a.m. and offer a variety of drinks.
Sources:
Nightlife in Greece: Best Destinations, Bars & clubs | Greeka.com