You will need pesos in Sayulita. There are now 4 ATM machines in Sayulita. Some places may take a little bit of US dollars to pay for something, but the exchange rate they will give will not be good. Only a couple places take credit cards. There is a new money exchange establishment off the town plaza. To get the best exchange rate, you need to either get money in the airport or pick it up at a bank on the way.

Once you are here, the closest bank is in Bucerias, about 20 minutes south. The exchange rate is always changing. It is now 1.00 USD to 10.50 Mxn.