ESTA for the United States: when to apply, how long approval lasts and when a new one is needed

Travellers using the Visa Waiver Program to visit the United States need an approved authorisation through the Electronic System for Travel Authorization (ESTA), an automated system that U.S. Customs and Border Protection (CBP) uses to determine eligibility for the programme. The Visa Waiver Program allows stays of 90 days or less without first obtaining a visa.

CBP says an application can be submitted at any time, but preferably as soon as a traveller begins planning a trip. Approvals are typically granted for two years or until the applicant's passport expires, whichever is sooner. Since 1 April 2016, all travellers must have an e-passport to use the programme.

The authorisation is not permanent in every case. CBP lists situations that require a new ESTA, including being issued a new passport and changing one's name. Passengers who renew a passport before a trip to the United States should therefore check their authorisation status well before departure.

CBP also makes clear that an approved ESTA is not a visa, and that travellers without approval may be denied boarding, face delayed processing or be refused admission. It adds that using a private service to apply will not speed up approval.

Eligibility depends on nationality and individual history, so travellers should confirm the current requirements on CBP's official pages before booking.