It's in all debit/credit transactions. This is a info for merchants. Customers don't see it visible on their final invoice.So, credit cards only? I rarely use my US credit card here but I do use my DR debit card here a lot. Never seen the extra 2% on my receipts or bank statements(?).
The 2% is an "anticipo tax" that's paid automatically in every transaction directly to the DGII and managed through the credit card processors.