The ESTA (Electronic System for Travel Authorization) is a legal permit, authorizing successful applicants to enter the United States under the Visa Waiver Program (VWP). Applicants from 39 countries, including the UK, Australia, and Ireland, are able to visit the US visa-free with the system.
ESTA allows US Customs and Border Patrol to pre-screen travelers and authorize them to travel to the United States.
However, a border control officer will check the traveler’s passport, ESTA, and any other travel documents upon arrival in the US. They will make the final decision as to whether the individual may enter the country.
In the vast majority of cases, ESTA holders are granted entry to the US.
If a traveler’s ESTA is denied, they may reapply. The most common reason for refusal is small errors on the application. It is recommended to double-check all answers before submitting the online form to avoid having to repeat the process.
If there is some other problem or if the traveler experiences multiple rejections, they may still apply for a B1/B2 visa at a US embassy. This is a much longer process than the online ESTA application and involves attending an interview and providing more documentation.
For this reason, it is advisable to ensure that there are no errors on the ESTA application that could cause it to be denied, as it is much quicker and easier to obtain than a visa.