Nonresident alien Hard Money Loan Investor. income Tax impact.

[Pablo Barrios]

Hi, I am a Nonresident alien with an Investment in a Promissory Note guaranteed with a Deed of trust (in other words, a Hard Money Loan Investor in Real Property in California).

I would like to be advised about the tax implications, more precisely if I had to pay Income Tax on the Interest received from the Promissory Note. I do not have any other business or trade in U.S., other than this. 

I have read the Publication 515 and 519 of the IRS and it would seem that this kind of Interest are exempt from the Withholding Tax, as well as the Income Tax Return, as they are considered "Portfolio Interests" and therefore non taxable income. 

I would really appreciate your unvaluable comments. Thank you very much.