We exchanged for some Canadian dollars at the border and were surprised by the poor rate of 99 cents per US dollar. Most if not all businesses take US dollars, so there is no need to exchange for Canadian dollar and lose money on it. It seems that businesses have accepted US dollars all along and treat it as Canadian dollar. So historically, this would be a big loss for the customer--my wife (then girl friend) and I were in Canada 11 years ago and the exchange rate was 1.5 Canadian dollars per US dollar. I also tried using credit card and American express charged some foreign trasaction fee while capital one did not. In any case, credit card would be better than 1 canadian dollar per US dollar but the difference among all means of transaction is small, 99 cents to $1.02. So lesson is, use your US dollars or use credit card, don't exchange for Canadian dollars.