Can i use my samsung impression in a different country without a big bill?

I'm going to France and Italy over spring break and i need to know if i can use my phone there. I have a Samsung Impression. I know its a world phone, but does it cost more to call or text someone in the US while i'm there?Can i use my samsung impression in a different country without a big bill?
Once you cross the border its international. I would call the company and ask. It costs more money to call and text people when you're out of the country no matter where the receiver is. If you're in France and call a buddy in France, it'll cost more money. If you're in France and you call someone in the U.S it'll cost more money. Unless you have some sort of international plan set up. Then it really doesn't matter. It costs the same amount to text someone out of the country if it is part of your plan.