Although the Dominican Republic has their own currency, the US dollar is widely accepted as well as credit cards. Now please keep in mind that the only traveling that I do is from the airport to the resort and back; so I can’t say for sure if this is true throughout the whole country.
We normally bring an assortment of bills with us, but mainly ones and fives. And the money that we bring is normally just for tips or very small purchases. It has been my experience that for larger purchases, it’s best to charge them on your credit card. I’ve found that you will get a better exchange rate than with the rates at your resort. Sometimes though, you will get a discount if you pay in cash. It’s also a good idea to see if you could get a discount if you pay in American dollars for whatever item or service you are purchasing.
If you need cash, most resorts or resort areas have ATM machines. These machines will charge you for their use and dispense only Dominican Republic Pesos (DOP). And there is a minimum withdrawal amount usually about 10,000 DOP’s or roughly $220. The current exchange rate as of today is $1.00 = 41.5506 DOP.
Whenever purchasing anything in the Dominican, make sure you know exactly how much the item or service is and in what currency they are charging. In the resort shops, the price tags are generally in DOP. If you ask, they will convert the price for you (the clerk will take out a calculator) and tell you how much you need to pay in American dollars.