An ESTA is also mandatory when passing through the USA
Are you only travelling to the USA on a transit to another country? Even then, you are required to possess this travel authorisation before you are allowed to board your flight. On a transit with a group of people? Then each traveller, including children, need their own ESTA. Does your transit only consist of a single transfer at a US airport and you don’t need to leave the plane for your transit? It is still mandatory to apply for an ESTA. In the ESTA application form, you can indicate that it concerns a transit.
Transit through the US often cheaper
Many travellers flying to the US are often on a transit to another North or South American country. Oftentimes, flying through the US is cheaper than going straight to the country of destination, because there are a lot of major airlines that use set routes and larger airplanes in the US. From the US, smaller planes and less frequent flights are used to travel to the country of destination. Another reason for a transit through the US might be because countries in South and Middle America refuse straight flights from other countries across the sea.
Transit through the US with ESTA
The easiest way to be allowed on a flight to the United States on a transit is by applying for an ESTA. If it is granted, it is not necessary to apply for a US visa. The ESTA is cheaper than a visa (£39,95), easier to apply for (through an online form), and is granted much faster (often on the day of applying). It is also possible to use a single form to apply for ESTAs for an entire travel company. It is important to indicate during an application that you are on a transit. This way, you will not be asked for a staying place in the United States.
Transit visa for the USA
A transit through the USA can also be made without an ESTA, if you possess a transit visa. The transit visa for the US is officially known as a C-visa. Applying for a transit visa cannot be done online through the application form, but must be done at the US embassy. Because of this administrative process and the higher price for the visa, almost no one chooses for a transit visa these days, and the ESTA is by far the most popular choice for transits through the USA.