Four people were arrested and 523 were fined for failing to wear a face mask on Tuesday, police said on Wednesday.
A total of 78,627 checks were conducted throughout the day, including 36,483 at Athens airport, police added.
Of the 523 people found not to be wearing a face mask, 519 were fined a sum of €300 and four were fined €150.
In Thessaly, a postmaster was fined €5,000 and ordered to close for 15 days after he was found serving a large number of customers on his premises.
Likewise in Crete, to café owners were fined €5,000 euros each, and ordered to close for 15 days, for serving customers without Covid passes.
As of December 24, masks are obligatory in both indoor and outdoor areas – including churches – while a double mask or a KN95 is required to travel in public transport or visit a supermarket.