Excerpted from the Mexico Career Guide
Since November 2012, Mexico's immigration system has been changed as a result of the enforcement of the new Migration Law. The number of visa categories was reduced to three: visitor, temporary resident and permanent resident. Mexico eliminated the option of changing visa status in country unless it is requested for family reunification or humanitarian reasons. Consequently, foreign nationals must obtain temporary residence visas before entering Mexico if they intend to stay for more than 180 days.
Further, Mexican companies must register with the National Migration Institute (Instituto Nacional de Migración) (INM) in order to hire foreign workers before they apply for temporary residence. Old immigration documents, including the non-immigrant and immigrant documents issued before the new immigration law was passed, will be valid until their original expiration. Foreign nationals with old non-immigrant and immigrant documents will be treated as temporary residents under the new regulations.
Business Visitor Visa
Business visas are available for those visiting Mexico to attend meetings, promote sales, visit associates, make contract arrangements, perform market research, seek representatives, purchase goods, or make or seek investments. However, business visa holders are not allowed to engage in profitable activities, employment or work of any kind. Business visas can be valid for up to one year. Some foreign nationals can enter Mexico exempted from the need for business visitor visas for a period up to 180 days and for multiple entries.
Student Visitor Visa
A student wishing to study in Mexico can apply for a non-immigrant student visa, which can be valid up to one year. Foreign nationals who enter Mexico on student visas may not engage in paid employment. Students cannot work or engage in any remunerative or lucrative activity unless an internship forms part of the study program. To qualify for the visa, an applicant must be enrolled in full-time studies.
If the purpose of visiting Mexico is working and the foreign national will receive a salary or payment, he/she must apply for prior authorization to the National Immigration Institute (INM) in Mexico. The foreign national will receive an authorization number (NUT number). As soon as the NUT authorization has been issued, the applicant must be in contact with the consulate in order to schedule an appointment and process a visa.
Before applying for a working visa, it is required to have a job, as the employer must submit the work permit application at any office of the INM in Mexico. The prospective employer will need to provide all necessary documentation to the INM. The consulate is able to issue a visa allowing the holder to work in Mexico once the National Migration Institute has issued a work permit. If the INM issues a work permit, it will inform the employer. The applicant must then contact the consular section in order to make an appointment for an interview.
Ministry of Foreign Affairs
This is just a short sample of what you’ll find in over 100 pages of information in the complete Mexico Guide.