Entering the United States
A visa allows a foreign citizen to travel to a U.S. port-of-entry (generally an airport) and request permission to enter the United States. A visa does not guarantee entry into the United States. The Department of Homeland Security (DHS), U.S. Customs and Border Protection (CBP) officials at the port-of-entry have authority to permit or deny admission to the United States. If you are allowed to enter the United States, the CBP official will provide an admission stamp or a paper Form I-94, Arrival/Departure Record. Learn more about admissions and entry requirements, restrictions about bringing food, agricultural products, and other restricted/prohibited goods, and more by reviewing the CBP website.
Visitors are not permitted to accept employment or work in the United States.
No assurances regarding the issuance of visas can be given in advance. Do not make final travel plans or buy nonrefundable tickets until you have a visa. Please apply well in advance of your travel date.
Unless canceled or revoked, a visa is valid until its expiration date. Therefore, a valid U.S. visa in an expired passport is still valid. If you have a valid visa in your expired passport, do not remove it from your expired passport. You may use your valid visa in your expired passport along with a new valid passport for travel and admission to the United States.