Q. I am travelling to South America via Miami. On the way out I just change planes there, but coming back I will be stopping off for a couple of days. I registered for an Esta for the way back, with my inbound dates, but someone said I need it for outbound journey too - even though I'm not leaving the airport. Is that the case? I tried to buy a second one to cover me but it just wouldn't go through.
A. Unlike pretty much every other country, the US demands a visa or its online version, the Esta (Electronic System for Travel Authorization) from foreign travellers who are merely transiting between two international flights. You must clear immigration and customs before checking in for your connecting flight. But there should be no problem with your journey. The fact that you have an Esta means you have been pre-cleared by all the various US security agencies, with a two-year window from the date approval is granted (that's why your application for a second one failed, because you are already welcome to visit).
For your impending journey, go to the official website esta.cbp.dhs.gov and click on "Retrieve Application". You should be able to update your details, amending them with the dates for the outbound journey.
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