Offshore reporting problems rarely start with dramatic tax fraud stories. More often, they begin with something ordinary: an inherited account, a foreign pension, signature authority for a family business account, or a taxpayer who assumed a foreign bank was “already reporting everything.” Then a filing gets missed, an account gets left off an FBAR, or Form 8938 never gets attached to the return.
That is where expensive exposure can begin.
The federal offshore reporting system is layered. A person may have to file an FBAR with FinCEN, report foreign financial assets on Form 8938 with the IRS, disclose foreign-source income on an income tax return, and retain account records for years. Those rules overlap, but they are not identical. The result is that a relatively small misunderstanding can turn into multiple filing issues, multiple years of noncompliance, and significant penalty risk.
If you are looking for a broader overview first, it may help to start with this guide on foreign account reporting and undisclosed account risk.
In this post, you’ll learn the six offshore reporting mistakes that often create the most costly exposure, why they happen, and what they often mean when an attorney begins evaluating a case.
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The FBAR filing threshold is surprisingly low. A U.S. person with a financial interest in, or signature authority over, foreign financial accounts generally files an FBAR if the aggregate value of those accounts exceeds $10,000 at any time during the calendar year, according to FinCEN’s official guidance (FinCEN). That threshold is not per account. It applies to the total across reportable foreign accounts.
The FBAR is also separate from Form 8938. The IRS explains that Form 8938 does not replace the FBAR; some taxpayers file both, depending on the facts and thresholds (IRS). For Form 8938 alone, the IRS states that certain unmarried taxpayers living in the United States may have a filing obligation when specified foreign financial assets exceed $50,000 on the last day of the tax year or $75,000 at any time during the year (IRS).
Penalties can add up quickly. The IRS states that failing to file a complete and correct Form 8938 can trigger a $10,000 initial penalty, with continuation penalties that can rise by $10,000 for each 30-day period after IRS notice, up to a $50,000 maximum continuation penalty (IRS). On the FBAR side, the IRS’s internal guidance explains that civil penalties may apply to non-willful and willful violations, and that willfulness can include not only knowing conduct but also recklessness or willful blindness (IRS).
That combination—low thresholds, overlapping forms, and steep penalties—is why offshore reporting mistakes often deserve early legal review.
This is one of the most common mistakes.
Some taxpayers look at each foreign account individually and conclude that none of them exceeds $10,000, so no FBAR is required. But FinCEN’s rule focuses on the aggregate value of foreign financial accounts. If the combined value goes above $10,000 at any point during the year, the filing obligation may be triggered (FinCEN; FinCEN FBAR Instructions).
That misunderstanding can affect more than checking the wrong box. It can create a chain reaction: