Per the IRS website, United States persons are required to file an FBAR if they "had a financial interest in or signature authority over at least one financial account located outside of the United States; and if the aggregate value of all foreign financial accounts exceeded $10,000 at any time during the calendar year to be reported."
There are some exceptions and other rules regarding Foreign Bank Account Reporting. If you have questions, be sure to ask your tax advisor and make sure to not forget that deadline!
Please note that every individual tax situation is unique. Before you embark on any specific tax position, it is important to consult your tax adviser. The above isn't and shouldn't be construed as tax or professional advice.