How many days in advance should I apply for ESTA?
21 Aug 10:41

How many days in advance should I apply for ESTA?
When you wish to travel or stay on the mainland United States or islands in US territory such as Hawaii for up to 90 days, you must apply for an ESTA.
While you can enter Guam and Saipan in the Mariana Islands without an ESTA, the maximum time you can remain without one is 45 days. If you apply for an ESTA, you can stay for up to 90 days. Although there are no precise restrictions governing how many days in advance you must apply for ESTA, the results of your application are usually received within three days, or 72 hours.
It may take even longer in some situations owing to reasons such as system maintenance or system difficulties on the US side, as well as when the server is unavailable.
We accept ESTA applications 24 hours a day, 365 days a year. The results of your application should be provided within three days, although we encourage applying for ESTA as soon as you plan to travel to the United States.
Why is ESTA required to travel to the U.S.?
Some may ask why you need to apply for an ESTA in order to go to the United States.
In January 2009, the United States began requiring visa-free visitors to apply for the Electronic System for Travel Authorization (ESTA), for reasons including security in the United States and preventing terrorism in the United States and throughout the world.
With the implementation of ESTA, it became feasible to verify the following items ahead of time by controlling and registering information on visitors travelling to the United States for short stays under the visa waiver program online before they left for the United States. These items are meant to confirm in advance if an individual applicant has a status that allows him or her to enter the United States without a visa or whether he or she could represent a risk to the country if allowed.
Nationals of countries eligible for the visa waiver program may enter the United States for up to 90 days for sightseeing or business purposes without applying for or acquiring a visa. ESTA is a required travel permit for anyone entering the United States without a visa. When transferring planes to another nation at an airport in the United States, ESTA is also necessary. In certain occasions, travelers who did not apply for ESTA before to departure have been denied entrance to the United States at immigration screening or have been denied boarding their flights.
If you want to visit the United States or change planes at a U.S. airport, you must apply for ESTA. Those who hold a U.S. visa do not need to apply for ESTA.
TRAVELING TO THE UNITED STATES?
Do You Have U.S. ESTA VISA Travel Authorization? If You Have ESTA Application, Check if it is Still Valid!
Can I apply for ESTA even on the day of travel?
Because they were ignorant of the ESTA program or neglected to apply earlier, many tourists apply for ESTA on the day of travel or just before it. Although in some circumstances ESTA screening proceeds well and travelers gain authorisation to fly without a hitch, in others screening may be placed on hold for even a short period, implying that they will not receive the results of screening smoothly.
Please keep in mind that applying for an ESTA on the day of flight does not ensure easy passage.
The ESTA is a mechanism that does not need the passenger to apply. If you are too busy to apply, you can have an agent do it on your behalf. If you have any questions, please contact the Center. If you apply for your ESTA with us, we will notify you of the screening findings through email.
Apply for ESTA at least three days before you travel
Although it usually takes three days, or 72 hours, for the results of screening to be finalized after you file for an ESTA, it may take longer during busy travel months like March and August, as well as during large-scale system maintenance. In such instances, the US recommends filing for an ESTA at least three days before your trip.

You will need to apply for a visa if your ESTA application is rejected
If your ESTA application is denied for any reason, you must apply for a visa.
B visas are primarily for travel for tourism purposes, E visas are for individuals seeking to stay in the United States primarily for business purposes, and L visas are for people transferring to work at firms in the United States. If your ESTA application is denied, you will need a visa to enter the United States, and it normally takes 1-2 months from the time you apply for a visa until you obtain one.
The main distinctions between an ESTA and a visa application, aside from the time necessary, are the quantity of papers that must be provided and whether or not you must attend a US consulate for an interview. In a variety of ways, applying for a visa takes substantially more time and money. As a result, we encourage that anyone visiting the United States for short-term travel or training apply for ESTA rather than a visa. If you replied “Yes” to any one of the eligibility questions while applying for an ESTA, you will be denied, Screening might take more than 72 hours. If you are denied permission to go to the United States after applying for an ESTA, double-check that you answered every question accurately and typed all of the numbers and letters correctly on the application, and then try to see and ascertain why your application was rejected. If it is evident that the denial was due to an error on the form, you must reapply for ESTA, wait at least 24 hours, and submit the information accurately. (You must pay the necessary fees to apply for ESTA again.) ESTA applications are accepted around the clock, 365 days a year.
Apply for an ESTA as soon as you intend to visit the United States.
How long is ESTA valid for?
The validity duration of an ESTA (Electronic System for Travel Authorization) is two years from the date of issue. However, if your passport expires during the next two years, your ESTA will expire at the same time. It is not possible to update the ESTA. If your ESTA has already expired, you must reapply for entrance into the United States. By re-application, the previous ESTA information is removed, and a new ESTA with a new expiration date is granted. Check out “ESTA expiration date and re-application” for further information on the ESTA expiration date.
TRAVELING TO THE UNITED STATES?
Do You Have U.S. ESTA VISA Travel Authorization? If You Have ESTA Application, Check if it is Still Valid!