|Although there are daily fluctuations, €1 (Euro) is currently equal to about $1.28 USD, so, basically, you add about 1/3 to the cost of any item you see on a menu or in a store to determine what it will cost you in US dollars.
ATMs are easily found in all of the places we’ll be going, and for a small fee you can access your money as Euros (so you don’t need to do a currency exchange). I never change money or purchase Euro (technically the word ‘Euro’ can be either singular or plural) before going to Greece. I simply find an ATM at the airport when I arrive and get about two hundred Euro. Then, when I start to run low, I find another ATM and get more money. That way, I’m never carrying an excessive amount of cash. The downside of this approach is that I pay a bit more in ATM fees than if I extracted a lot of money at one time. For me, however, that’s a small price to pay for greater peace of mind.
Only in the last few years has it become possible to use credit cards as widely and in as many different kinds of places in Greece as in the US. Nonetheless, you should plan to use cash when you’re making small purchases at shops and fast food establishments. Where plastic is accepted, VISA or MasterCard are the preferred card types, but American Express is accepted at nicer establishments and for larger purchases.
Traveler’s checks are virtually unheard of and almost never used in Greece. Plan on using your credit card where you can and accessing cash at ATMs as desired.
You should contact your bank and credit card companies before departure to let them know you will be using your card(s) abroad—if you don't, your card(s) might be blocked.
and the basic banknotes