TN status (or TN classification; "TN" from Trade NAFTA) is a special non-immigrant classification of foreign nationals in the United States, which offers expedited work authorization to a citizen of Canada or a national of Mexico. It was created as a result of provisions of the North American Free Trade Agreement that mandated simplified entry and employment permission for certain professionals from each of the three NAFTA member states in the other member states. The provisions of NAFTA relevant to TN status were then carried over almost verbatim to the United States–Mexico–Canada Agreement that replaced NAFTA in 2020. A Canadian citizen or Mexican national with a job offer from a U.S. employer in certain defined professions and who meets the minimal education requirements for the relevant profession can work in the United States, for up to three years. The classification theoretically may be renewed indefinitely, although real-world complications may limit the number of times, or overall length of time, a foreign national might successfully be granted an authorized period of admission into the United States in the classification. For Mexican nationals, being granted admission in TN classification generally requires first being issued a TN visa at a U.S. consular post. In contrast, Canadian citizens, who are generally exempt from the usual requirement of U.S. federal regulations to obtain a U.S. visa in advance of requesting admission to the U.S. (with limited exceptions), generally simply present their relevant paperwork directly to a U.S. Customs and Border Protection officer when seeking a new period of authorized admission into the United States in TN status. For both Mexican nationals and Canadian citizens already present in the United States and maintaining lawful immigration status in a classification other than TN, TN classification can also be granted through a "Change of Status" process initiated by a U.S. employer's petition for TN status on behalf of that prospective or current employee. Canada's corresponding NAFTA work permit for U.S. citizens and Mexican nationals is sometimes unofficially also referred to as a TN status or TN visa, although this name is technically only a creation of U.S. law. TN classification bears a similarity, in some ways, to the U.S. H-1B classification, but also has many unique features. Notably, H-1B classification allows for "dual intent" to obtain permanent residency in the United States, while TN status does not. As such, a TN status holder may become ineligible for U.S.