Correct Identification/the Passport:
For the latest Mexico entry requirements: Contact the Embassy of Mexico website or call the Embassy at (202) 736-1000 or any Mexican consulate in the US.
Land travelers must have a valid US passport accompanied by acceptable photo identification, such as a state or military issued ID. A passport or passport card is the best method of providing this information.
All US citizens are now required to present a passport book, passport card, or WHTI-compliant document when entering or re-entering the United States. Obtain a US Passport card now (NOTE: Only valid for land/sea travel).
You need your passport to be able to get back into the US after visiting to Mexico. The passport application process requires that you submit an official passport photo. A good place to get one is at a local pharmacy. All passport applicants must also submit an original copy of a state issued birth certificate. Please note, if your birth certificate was issued by a hospital, the US Department of State will not accept it. In order to save yourself some frustration, we recommend you order a new official birth certificate directly from the state where you were born. The passport application process typically takes anywhere from a couple of weeks, up to a month or more, so it is best to get started well in advance. If you are pinched for time or on short notice, you can elect to pay extra money to expedite the process. You can get more information about applying for and obtaining a passport by visiting www.travel.state.gov.