Currently, many countries citizens (including US Citizens) can enter the Schengen area without a visa. In fact, together with the United States, there are more than 60 countries that are visa-free when it comes to visiting Europe.
Until the year 2021, there's no specific authorization required for American citizens except a valid passport.
The visa-exempt policy covers only short stay terms (less than 90 days), for a longer duration of stay a Schengen Visa is required.
From the year 2021, US citizens willing to travel to Europe will need to apply for an ETIAS, an online travel authorization similar to the one already introduced like other countries.
The ETIAS (European Travel Information and Authorization System) will be a new requirement for all American Citizens. Every component in a group, without any distinction of age, will need to comply with this requirement.
Throughout the travel authorization validity period (3 years), ETIAS visa will make possible for USA travelers to enter multiple time any of the Schengen zone member countries which apply to this visa as many times as necessary.
The restrictions imposed when traveling to Europe from the USA will not change, these include limited importing and exporting quantities of tobacco, alcohol or perfume and declaring amounts of currency above EUR 10000.
As mentioned above, starting from 2021 every US Citizen traveling to Europe has to apply for an ETIAS visa.
The ETIAS application is a simple process that only requires:
The passport used in the ETIAS application form must be valid for 3 months beyond the period of intended stay in Europe. Furthermore, the ETIAS application will also collect biographical information like:
Despite the quantity of data that the applicant has to provide, the EU Commission stated that ETIAS Visa Application form should not take more than 20 minutes to be completed in all its parts.
American citizens traveling to Europe must be sure to have valid biometric travel documents (like a biometric passport) while applying for an ETIAS. This kind of machine-readable document stores information about the holder such as a photo of the passport holder, passport data, and personal data. The EU will not copy over such information from to the ETIAS visa system during the application process.
EU commission didn't make it clear yet if biometric travel documents will be the only one supported during an ETIAS application for American Citizens. Apparently, other documents like The US Passport Card should not be qualified to be accepted during the application process.