Errors on an ESTA application may not only cost an applicant money, but they could also negatively affect an applicant’s ability to embark on a trip to the United States. Mistakes can cause ESTA denials, thereby increasing the likelihood a traveler won’t get an authorization to enter the country under the ESTA Visa Waiver Program (VWP). Given the many different kinds of errors that could occur, ESTA applicants should always take the greatest care when filling out the ESTA application form.
Below we set out the 10 most common yet avoidable mistakes people make on their ESTA application forms:
 Entering the wrong passport number
Passport numbers differ substantially from one country to the next. A very common mistake ESTA applicants make is to enter too few or too many digits on the ESTA application or to enter the wrong passport number. This is a problem because after submitting the application form you are not able to edit your passport number. You will have to fill out and submit a new application form.
 Entering the wrong information under Passport Issuing Country or Country of Citizenship
Applicants often get confused with these two fields. For most people, however, they are the same. If you are a citizen of Thailand, your passport will most likely also be issued by Thailand. If you also have a passport that was issued by another country, there is a separate field for this information.
 Entering the wrong date of birth
If you make a mistake with the day, month, or year of your birth on the ESTA form you will have to submit a new application since this information can not be changed once you have submitted the form. That is why it’s so important to double-check everything you have entered on the form before hitting the submit button.
 Wrong gender
Individuals are currently identified on their passports as either male or female. If you enter something different on the form your ESTA application could be denied and there might not be enough time to submit a new application before your departure.
 Neglecting to enter your middle name
On the ESTA application form, there is a field called ‘Given Name’. This is where you should enter both your first and middle names. If you are e.g. called ‘John Peter Brown’ (where Brown is the surname) you should enter John Peter in the Given Name field. Failure to do so will mean that you have to submit a new application.
 Making a spelling error when entering your last or first name
If for whatever reason, you make a spelling mistake when entering your first or last name, you will have to send in a new ESTA application. No authorization will be given if the information provided on the ESTA form differs from your passport information.
 Giving the wrong answer to an eligibility question
If you mistakenly respond with a ‘yes’ to one or more of the ESTA eligibility questions (mental disorder, criminal record, drugs, etc.) your ESTA request could be denied. And if you answer ‘no’ while the correct answer is in fact ‘yes’, you could be denied entry to the U.S. for as long as five years.
 Wrong email address
If an applicant enters the wrong email address on their ESTA application form, CBP will not be able to contact them about the outcome of their application. If he or she, however, later realizes that the wrong email address was entered on the form, they will be able to correct the mistake.
 Failing to check on your ESTA status
Applicants are able to check their ESTA application’s status free of charge. You should check the status of your ESTA application 24 hours before your trip to the U.S. starts to make sure you don’t get a nasty surprise when you try to board the flight or boat to that country.
 Other mistakes on the ESTA application form
There are many other fields on the form where applicants can (and often do) make mistakes, or enter incomplete information. An example is the one where they have to enter information about their contact in the United States. This could be a hotel the applicant hasn’t booked yet or the booking has not been confirmed. In this case, you are allowed to enter ‘Unknown’ in text fields or ‘00000’ in numerical fields. You will be able to edit this information afterward.
From the above list of common mistakes people make on their ESTA application forms, it will be clear that most of them could easily be prevented. It’s perhaps a good idea to type out all your answers and to double-check everything before filling out the actual form to lower the chance of making mistakes on your ESTA application.