You can only find ATMs in the city of Sabang, which is about 40 minutes from Gapang and Iboh beaches. Two of three ATMs in Sabang should accept mastercard and have a maximum withdraw facility of 500,000 so consider bringing lots of cash with you. Recent experiences show, that mastercard usage is dependent on the bank issuing the card. Get the necessary cash in Banda Aceh if you don't want to rely on Western Union money transfer with banks in Sabang.
