Mexico entry requirements and Cancun travel checklist

As of 2010, every foreign national visiting Mexico is required a valid, currently unexpired passport to enter the country. In the past, U.S, citizens could enter with any official proof of citizenship document such as birth certificate or a green card, however this is no longer the case. Without a passport that is valid for at least 180 days after you arrival date, you will not be allowed into the country. You must have your passport with you from the moment you arrive at the airport in your home country. There are no exceptions for minors.

When your arrive to Mexico you will be given a tourist card (form FM-T). You need to fill this short form that includes: name, number of days to be spent in Mexico, passport number, final destination of your trip, city of origin, dates of travel and means of arrival. Business travelers will also be given a FM-N 30 Days form, which will allow them to do business for a period of up to 30 days, but you cannot accept a job. Those who need to enter the country for reasons other than tourism and business, or to stay for more than 180 days, will need to apply for a visa at a Mexican consulate in their home country before coming to Mexico.

It is important that you keep this form safe during your trip, as you will be required to turn it when leaving the country. If you lose or damage it you will be charged a $24 USD fee to replace it.
When traveling with minors, Mexican law requires that any non-Mexican citizen under the age of 18 departing Mexico must carry notarized written permission from any parent or guardian not traveling with the child to or from Mexico. This permission must include the name of the parent, the name of the child, the name of anyone traveling with the child, and the notarized signature(s) of the absent parent(s) as well as the reasons for the trip.
For the latest entry requirements go to: Mexico-entry-requirements

Mexico Visa Policy permits citizens of the countries listed below to travel to Mexico without a visa:
Andorra, Anguila, Argentina, Aruba, Australia, Austria, Bahamas, Barbados, Belgium, Belize, Bermuda, Brazil, Bulgaria, Cayman Islands, Canada, Chile, Colombia, Commonwealth countries, Costa Rica, Croatia, Cyprus, Czech Republic, Denmark, Ecuador, Estonia, Faroe Islands, Finland, France, French Guyana, Gibraltar, Guadalupe, Germany, Greece, Greenland, Hong Kong, Hungary, Ireland, Iceland, Israel, Italy, Jamaica, Japan, Latvia, Liechtestein, Lithuania, Luxembourg, Macao, Malasia, Malta, Micronesia, Monaco, Netherlands, New Zealand, Norway, Perú, Poland, Portugal, Rumania, San Marino, Singapore, Slovakia, Slovenia, South Korea, Spain, Sweden, Switzerland, Trinidad, Turks and Caicos, United Arab Emirates, United Kingdom, Uruguay, USA, Venezuela.

What should you pack?

Casual, comfortable clothes, like T-shirts and shorts
Business casual attires for visiting some restaurants or night clubs
Any important medications: bring enough for your whole trip
Basic first aid kit: bandages, ointments, aspirins, and other over-the-counter medications you normally use in case you need them. Pack them in one kit and do not mix them with your other things. (You can buy medication in Mexico easily, but you cannot buy antibiotics without prescription)
During the winter you may need a light sweater or sweatshirt for the occasional cool evening
Raincoat or waterproof windbreaker in case of rain
At least 2 swimsuits
Walking shoes or sandals for the beach (the sand gets really hot, shoes are important)
A camera: you may use your smartphone or you may want to bring a proper camera, water resistant or waterproof cameras are a plus
Sunscreen: bring plenty of sunscreen, Cancun is a hot, tropical destination where the sun shine bright most of the year. It is very important for getting the most from your vacation to avoid getting sunburn.
You will find that more and more places have banned non-biodegradable sunscreens in recent years to protect the environment. If you bring non-biodegradable sunscreen it may be taken from you at one point. We strongly recommend bringing biodegradable sunscreen to ensure you can use it everywhere you go.
Insect or mosquito repellent: as with sunscreen, non-biodegradable insect repellents are banned in many places
Sunglasses
Dry-bags, ziplock bags, or other waterproof containers to protect your important belongings from water and sand while at the beach
Snorkel equipment: If you plan on doing a lot of snorkeling, having your own gear would be a good investment
A backpack comes very handy for tours and excursions
Reusable water bottle
Reusable straws: many places have stopping using plastic straws and they are soon to be banned in the state and not every place offers an alternative