The currency in Mexico is the Mexican peso. U.S. dollars are widely accepted. Canadian currency and traveller's cheques are not widely accepted worldwide.Take Caution when using bank or credit cards as card information can be copied by unscrupulous vendors. Ask to swipe your card yourself or make every effort to ensure that it is only run through once. Make sure you obtain your copy of the transaction slip. If you use an ATM, do so during business hours at a location inside a bank, supermarket, or large commercial building. Check with your bank for information on ATM services in other countries. You can also check the VISA ATM locator page or the MasterCard ATM locator page for the addresses of ATMs around the world. Your bank can advise if you need a new personal identification number (PIN) for overseas access to your account. Credit cards and debit cards should be used with caution due to the potential for fraud and other criminal activity. ATMs should be used during business hours inside a bank, supermarket, or large commercial building. Leave copies of your card numbers with a family member in case of emergency.