Update: U.S. Customs and Border Protection (CBP) has announced that real-time approvals for the Electronic System for Travel Authorization (ESTA) will no longer be available. Travelers to the U.S. from Visa Waiver Program (VWP) countries who do not already have valid ESTA authorization are now advised to apply at least 72 hours prior to travel to allow sufficient time for processing.
ESTA Process: The application is filed online at https://esta.cbp.dhs.gov/esta/. This site can also be used to confirm the status of prior applications. Once approved through ESTA, VWP country nationals are authorized to travel to the U.S. for up to 90 days without requiring a visa. Individuals without a valid ESTA approval or another valid entry document (such as valid US visa, green card, or reentry permit) will not be allowed to board their US-bound flight.
Background: ESTA is an automated system used to “determine the eligibility of visitors to travel to the United States under the Visa Waiver Program (VWP) and whether such travel poses any law enforcement or security risk.” EIG recommends that eligible travelers apply as soon as they are aware of any anticipated travel to the U.S., as prior travel history or possible criminal issues can result in a denial. Those denied under ESTA must then apply for a B Visa for business or tourist travel to the U.S. through a U.S. Embassy or Consulate, which can take a number of weeks to obtain.