Regardless of the reasons for a person to travel to the United States, it is necessary to obtain prior official authorization and regardless of whether the visit to the country is of short duration.

In the case of a stopover in the United States or a visit of less than 90 days, it is not necessary to apply for a transit visa, but can instead obtain an electronic travel authorization issued by the U.S. authorities. This process can be completed in a few minutes through a simple online form.

Visas in the United States are classified in an alphanumeric system, where each category is given a letter and a subcategory is identified by a number. 

The type C visa is the one required for transit through the United States. In this context, there are five subcategories:

• C1: Designed for air or sea passengers.
• C1D: Designed for air and sea crew members.
• C2: Exclusively for personnel working at UN headquarters.
• C3: Intended for senior officials in transit.
• C4: Reserved for transit passengers under the pilot training program (ATP).

As is the case with any official authorization, the preparation of a dossier including several supporting documents is required. The items you will need to attach to your online visa application are as follows:

• Valid passport
• Completed DS-160 form
• Recent passport photograph
• Copy of your bank statement as proof of sufficient financial resources for travel
• Airline tickets to demonstrate the need for transit through the U.S.

If you are traveling with your family, each adult and child must apply for a C1 visa individually.

Obtaining a transit visa is a critical step in ensuring a smooth travel experience throughout the United States, no matter what your motivation for visiting this country. 

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