The fact that you're asking this question is of concern. Bring whatever funds you deem necessary for your visit.Declare it on the forms - no worries. If you try to hide the money, then civil /criminal penalties may ensue. Act accordingly.
A foreign national, upon arrival to U.S. can have virtually unlimited amounts of cash on him, as long as he/she declares it to U.S. Customs upon arrival. There is no "tax" or "penalty" that is due on an amount of money that has been earned or brought from abroad by a non-resident alien = a visitor from China or Uganda. You will only start paying taxes on the interest banks will pay you on the deposit of these monies in a bank account. With interest rates banks pay on time deposits being close to zero, I wouldn't worry about it.
Behar Intl. Counsel 619.234.5962 Kindly be advised that the answer above is only general in nature cannot be construed as legal advice, given that not enough facts are known. It is your responsibility to retain a lawyer to analyze the facts specific to your particular situation in order to give you specific advice. Specific answers will require cognizance of all pertinent facts about your case. Any answers offered on Avvo are of a general nature only, and are not meant to create an attorney-client relationship.
As my colleagues point out, the amount is not the issue. It is honestly declaring them on the form provided by customs. Be sure that if you carry money out of the US, including money you declared on the way in, that you file the declaration as well. I have had client's who failed to do so to their dismay.
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I agree with my colleagues. People that are caught not reporting true amount will feel the wrath of the law.
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