This is defined by U.S. tax regulations as an international person who has not been physically present in the United States for the amount of time required to be treated as a resident alien for Tax purposes. The status is determined based on the substantial presence test and the visa type of the individual. A nonresident alien for tax purposes has a completely different method of having tax withheld, completing tax forms and tax documents, and is eligible for very few and limited deductions and allowances when paying taxes. A nonresident alien for tax purposes must only report and pay tax on money that he or she receives from U.S. sources.