Your best exchange rate is via credit card. Last time I was in Canada was 1999. A US dollar was worth about 15% more than a Canadian dollar ($1 US would pay for $1.15 worth of Canadian goods). Another way to get this exchange rate is to use your ATM card in Canada to withdraw money. Withdraw $40 Canadian and you account only gets charged about $34.50. The US dollar is accepted in Canada. However, you will get Canadian coins in change, and US banks will only accept Canadian paper money (not coins). I have about $6.42 in Canadian coins somewhere at home, if you can use it (and I can find it).