If you wish to work in the United States for a temporary period you will require a nonimmigrant work visa. You cannot work on a visitor or business visa, or under the Visa Waiver Program (VWP).
Unlike some countries, the United States government does not issue work visas for casual employment. In general, work visas are based on a specific offer of employment. In most cases, a petition must be filed and approved by the United States Citizenship and Immigration Services (USCIS) before applying for the visa at a U.S. Embassy or Consulate.
What’s a U.S. work visa, and why do you need one? A visa is a document that provides authorization for travel to and admittance to the United States. Before visiting, working, or immigrating to the U.S., a citizen of a foreign country generally must first obtain a U.S. visa. The visa provides entry to the U.S. and, depending on the type of visa obtained, may provide authorization for employment in the U.S.
Having a visa does not guarantee entry to the U.S. However, it does indicate a consular officer at a U.S. Embassy or Consulate has determined you are eligible to seek entry for the specific purpose listed on the visa. Visas are obtained from the U.S. Embassy or Consulate that is closest to your residence abroad.
It is possible to become a permanent resident (Green Card holder) of the United States through a job or offer of employment. There is also a lottery program that provides a limited number of green cards for successful applicants.
However, some categories require a certification from the U.S. Department of Labor to show that there are not enough U.S. workers who are able, willing, qualified, and available in the geographic area where the immigrant is to be employed and that no American workers are displaced by foreign workers.
Also, there are specialized job categories that may enable you to get a visa based on your current or past employment. For example, first preference (EB-1) is priority workers, including “foreign nationals with extraordinary ability in the sciences, arts, education, business, or athletics; outstanding professors and researchers; or certain multinational managers and executives.”
U.S. Citizenship and Immigration Services has more information on how to apply for a Green Card.