I am a foreigner who resides in the US, and I am a 'US person' from a fiscal point of view. Therefore, it is my understanding I should not file a W8BEN. Nevertheless, I have a bank account and some investments in Europe and my bank insists I should file a W8BEN. What should I do? Can I get into trouble with IRS if I file the form, even if I do not claim any treaty? I am also concerned IRS might apply to my US incomes a 30% tax flat rate. Thanks a lot in advance.
W8-BEN, like most IRS forms, has a "who should use this form" section. If none of the descriptions fit you, print out a blank W8-BEN, attach a cover letter explaining in detail that the IRS is telling you not to file the form, and send it to the bank.
You will get in more trouble for not filing a form that you should than for filing a form that you shouldn't.
While you are a US person, the IRS is going to tax your worldwide income, although you can usually deduct any taxes paid to other jurisdictions. Do not try to hide anything from them.