Under the North American Free Trade Agreement (NAFTA), Canadian and Mexican citizens may enter the United States in TN status to engage in certain professional business activities. Only certain occupations may serve as the basis for receiving TN status to work in the United States.
Canadian and Mexican citizens may enter the US in TN status for up to 3 years. Upon completion of the initial time in TN status an extension of stay may be requested for up to 3 years. Unlike J status and H status, TN status does not have a cumulative total time limit and may be renewed indefinitely as long as the nature of the stay remains temporary.
Canadian citizens will apply for TN status at a US port of entry. They do not need to apply for or obtain a TN visa before being admitted into the US in TN status.
Mexican citizens will apply for and must obtain a TN visa at a US consulate before being admitted into the US in TN status.
8 CFR 214.6 contains the federal regulations that govern TN status.
The US Department of State provides information on applying for a TN visa as a Mexican citizen or entering the US in TN status as a Canadian citizen. Included in this information is an overview of TN status, requirements for both Canadian and Mexican citizens, how to apply for the actual TN visa, required documentation, and required visa fees.