It is recommended to apply for an ESTA (Electronic System for Travel Authorization) as soon as you know that you will be traveling to the United States. The ESTA application process is electronic and can be completed online, and it typically only takes a few minutes to complete. Once your application is submitted, it is processed within minutes, and you will receive an email with the results of your application within 2 to 72 hours.

It’s important to note that, you should apply for an ESTA visa well in advance of your trip, as there is no guaranteed processing time and it’s possible that your application may be delayed. Also, even if your ESTA is approved, it does not guarantee that you will be admitted to the United States. The final decision will be made by a Customs and Border Protection (CBP) officer at the port of entry.

It is also good idea to check the status of your ESTA before you travel and renew it if it’s needed, to make sure it’s still valid when you travel. Even if you already have an ESTA viza that’s still valid, you should reapply if your passport expires, or if there is any change in your name, gender, or citizenship status, or criminal records.

It’s always a good idea to plan ahead and have everything in order when you travel, it will help to ensure that your entry to the U.S. goes smoothly.