News report | | 20-02-2018 | ±3 minutes reading time

Applying for an ESTA is mandatory to travel to the United States. ESTA is a digital travel authorisation which states that the United States grants permission to enter the country.

This ESTA can be easily applied for online. It is mandatory to possess an ESTA document when you are at the airport of departure. When boarding, you will be asked for identification as well as a valid ESTA. If a passenger cannot present it, the airline cannot transport them. It is very important that you pay extra attention to digits and letters during the ESTA application.

Digits and letters in the passport number

To travel to the USA, you need to fill in an ESTA form. This makes it possible to travel to the United States without a visa. ESTA is therefore not a visa, but a digital proof that that you can travel to the USA. With the ESTA application, the traveller is registered as a visitor of the United States.

It is important during an ESTA application to correctly write down the passport information. There have been numerous cases where a traveller made a mistake writing down the passport information, forcing them to cancel their plans to travel to the USA. Some passport numbers use a combination of letters and digits, others have only digits or letters. British passport numbers, for example, are exclusively made up of digits. However, it still frequently occurs that travellers mistakenly fill in the letter O instead of the number 0. Irish passport numbers start with the letter P or L, followed by another letter and 7 digits. Like all other passport numbers, mistakes are frequently made here as well.

The document number on a British passportThe passport number on a British passport

The document number on an Irish passportThe passport number on an Irish passport

Writing down your passport number correctly is also important when booking your trip and flight ticket. That is why more and more transportation companies use an app, with which the traveller can scan their passport. This way, any confusion can be avoided.

Validity of the ESTA

Before travelling to the United States, it is important that all of the required documents are valid. The passport needs to be valid for the entirety of your stay in the USA. If the passport with which you plan to travel expires, the ESTA expires alongside it right away. You will then first need to apply for a new passport before applying for a new ESTA. You cannot simply apply for a new ESTA; not until you have acquired a new passport. British and Irish passports are generally valid for 10 years (adults) or five years (minors). If you notice the expiry date is imminent, apply for a new passport on time to avoid any trouble with your ESTA.

Tip for passport validity

Validity of the passport
The validity date of the passport is always indicated on the document. Check under the text “date of expiry”.

ESTA application

When applying for an ESTA, avoid commonly made mistakes like writing down an "o" instead of a "0". It is extremely important that all the information is fully and correctly written down for an ESTA application to get processed properly. Failure to do so will lead to the ESTA being declared invalid. An ESTA application costs € 49,95 per person. The application takes about five minutes. Airlines check beforehand whether the passport and the ESTA are valid. If either of them are invalid, the airline cannot take the traveller along to the USA. In that case, the traveller has to book a new flight. Avoid problems like that and double-check all the information on the passport and the ESTA application.

Please note: this news article about the ESTA for the USA is more than one year old. It might contain outdated information and advice, and no rights can therefore be derived from this article. Are you going on a trip soon and do you wish to do know what rules currently apply? Read all about the up-to-date information about the ESTA for the USA. is a commercial and professional visa agency, and supports travellers in obtaining, among others, the ESTA USA. acts as an intermediary and is in no way part of any government. You can also apply for an ESTA directly with the immigration service (21 USD per ESTA, via However, not with our level of support. If you submit your application via, our support centre is available to you 24/7. In addition, we manually check your application and all the documents you provide before submitting it to the immigration authorities on your behalf. If we suspect any errors or omissions while doing so, we will personally contact you to ensure that your application can still be processed quickly and correctly. To use our services, you pay us 21 USD in consular fees, which we pay to the immigration service on your behalf, as well as € 30,72 in service fees as compensation for our services, including VAT. Our services have saved many travellers from major problems during their trip. Should an application be rejected despite our support and verification, we will refund the full purchase price (unless an application for a previous ESTA USA was rejected for the same traveller). Read more about our services here.