Which of the following is essential for a nonresident alien completing US tax forms?

The essential requirement for a nonresident alien completing U.S. tax forms is an Individual Taxpayer Identification Number (ITIN). An ITIN is a tax processing number issued by the Internal Revenue Service (IRS) to individuals who are required to have a U.S. taxpayer identification number but do not have an SSN and are not eligible to obtain one. This includes nonresident aliens engaged in transactions that require tax reporting, such as earning income in the U.S.

While a Social Security Number (SSN) is typically used for U.S. citizens and eligible residents, it is not applicable to nonresident aliens who are not authorized to work in the U.S. Similarly, a work visa is related to the ability to work legally in the U.S. and does not directly deal with tax identification. An Employment Authorization Document (EAD) also pertains to employment eligibility but does not serve as a taxpayer identification number.

The ITIN allows nonresident aliens to comply with U.S. tax laws by properly reporting income and paying taxes, even if they do not meet the criteria for obtaining a Social Security Number. Thus, for nonresident aliens needing to file U.S. tax forms, obtaining an ITIN is a crucial step.