The official currency in Mexico is the Mexican Peso (MXN). However, the U.S. dollar is also widely accepted as a form of payment, especially in many tourist places such as Cancun, Tulum, Playa del Carmen, and Cabo San Lucas.
The best time to visit Cancún is from December to April during the peak season. Even though the crowds are heavier, you'll experience near-perfect weather and find some of the cheapest flight and room rates for a winter getaway at the beach.
The short answer is ABSOLUTELY YES, you need Mexican Pesos. You will need pesos for tips, souvenirs shopping, transportation like taxi/buses, tours, bar/restaurants, etc.
Mexican immigration authorities could ask you to present both your passport and entry permit if applicable at any point and may detain you while they review your immigration status if you are not carrying your passport and proof of legal status in Mexico, or if you have overstayed your authorized stay.
Cancun's Current Safety SituationAccording to the US State Departments, the Yucatan Peninsula is the safest region in Mexico for Americans in 2023. However, the State Department does have a travel advisory of “exercise increased caution” in the state of Quintana Roo.
Restaurants. In restaurants, 15% of a check is a good rule of thumb to follow; if you're in a big group you may find that a service fee is automatically added to the check (look out for that). If you feel you have been given particularly great service, 20% will be greatly appreciated.
Preparing your travel money options beforehand is the key to a stress-free vacation. Credit cards, debit cards, prepaid travel cards and cash are all accepted in Mexico. Outside of a few purchases like transportation fare or local shops, a credit card will be your best bet for everyday purchases.
During these months, you can expect relatively consistent good weather. Do make note that December to March is considered peak season in Cancun which means airfare and hotels are pricier.