Hello. How much time should one allow for departure from Santorini and Athens in July? For Athens, it will be for an AA international flight. With the busy season now, I did not know if 2 hours was sufficient for both. Thank you!
Two hours should be fine for the Santorini to Athens flight.
For your Athens to US flight you probably should allow more than 2 hours, especially if you have to check bags, as you will have to do passport control for Schengen zone exit. ( assumes your AA flight lands in the US)
The 'common wisdom' is 3 hours for international flights
Athens airport is smaller than you think. We arrived 2 hours early and had a lot of time waiting.
Airlines often have suggested arrival times for different airports on their websites.