Money Exchange Paris
 

Where can I exchange my unused Euros back into USD to get the best exchange rate?

No where. Try not to be in the situation. There is no good economical answer.

Toward the end of your trip be aware of how much you will need. Only change or withdraw what you need for the remainder of your trip. Use it as part of settling your hotel bill saving just enough for taxi and what you might spend at the departure airport. Spend the remainder at duty free or buying souveniers. At home sell it to your friends and co-workers who are going to Europe in the near future.

And/or, just save what remains for your next trip.

I agrre - just don't "over withdraw" your last few days so you don't have much left over.

And if you do end up w/ a few € - instead of exchanging them use them at the airport (you'll have at least 2 hours to kill) or on the flight for duty free and/or drinks.

You can also donate your leftover Euros (or any other currency you can't use.) Most airlines have envelopes to do so on the plane, and I think the funds go to Unicef. I usually give them my coins and some smaller bills, if I have any left.