The national currency of Mexico is the Peso.  When you see prices listed the listing will appear with the $ sign in front of the Peso amount.  Banco de Mexico is the nation’s central bank and issues coins and paper money that are legal tender.  Although in some parts of the country travelers may be able to spend U.S. Dollars, prices are almost always less expensive when using the Peso. The exchange rate fluctuates every day few cents up or few cents down. On-line currency converters  help travelers to have an idea and translate Pesos into their home country currency. Some places will take U.S. Currency in Mexico, but the exchange rate may not be the best, but stills good due to the competition  so ask ahead of time.  "Small Unmarked Bills" is also the operative phrase.

    Automatic teller machines (ATMs) often provide the best exchange rate because they give you the official interbank rate. Make sure to call your bank and your credit card companies to let them know of your travel plans as they may restrict your card usage, when charges from Mexico appear, to protect you from fraud. Be sure to find out the transaction fees for using either credit or ATM cards.

    Be very stingy with your lower denomination Mexican Paper Currency! Always try to use the larger denominations first because it is often difficult to find change. You don't want to be stuck trying to pay a fourty Peso taxi fare with a two hundred peso bill when the taxi driver says he does not have enough change.

     For many years, the approximate exchange rate between pesos and dollars was 10 pesos to one dollar.  Mental conversion of pesos to U.S. dollars was easy:  you could just move the decimal point one place to the left.  For example:  $100.00 in pesos meant $10.00 in U.S. dollars.  As of this writing, however (March, 2009), the peso has slipped relative to the dollar and the ratio is approximately 14:1.  Thus, an easy method for conversion is to multiply the number of pesos by 7 and move the decimal point two places to the left.  Example:  400 pesos x 7 = $US28.00 (approximately.....the full multiplier would be something like 7.14, but that's a bit harder).

    The current coins & notes in circulation and use are as depicted below: