From Greek Embassy website :-
"British and all other EU passport holders travelling to Greece do not require a visa and these nationals may travel to Greece without a visa provided that the passport is valid for the intended period of stay in Greece.
Providing that the stay in Greece is for no more than 90 days, nationals of the following countries also do not, require a visa to enter or transit through Greece or transit through a Greek airport, providing also that the passport is valid for at least 3 months from the day of return from Greece.The list of countries is as follows:
Andorra, Argentina, Australia, Bolivia, Brazil, Brunei, Bulgaria, Canada, Chile, Costa Rica, Croatia, Cyprus, Czech Republic, El Salvador, Estonia, Honduras, Hong Kong – blue and red passport holders, Hungary, Iceland, Israel, Japan, Latvia, Liechtenstein, Lithuania, Macao, Malaysia, Malta, Mexico, Monaco, New Zealand, Nicaragua, Panama, Paraguay, Poland, Romania, South Korea, San Marino, Singapore, Slovakia, Slovenia, Switzerland, United States, Uruguay, The Vatican and Venezuela. "
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