IRS Audits and Cook Islands Trusts

IRS examinations of Cook Islands trusts follow a predictable pattern. The IRS already knows the trust exists through FBAR filings, Forms 3520 and 3520-A, Form 8938, and FATCA reports from the foreign financial institutions holding trust accounts. An audit does not mean the IRS suspects fraud—it means the IRS wants to verify that the reported numbers are accurate and that the trust is being treated correctly for tax purposes.

A Cook Islands trust that has been properly reported every year since formation is in a different position from one with compliance failures. For a compliant trust, the audit is a documentation exercise. The problems arise when the trust has not been reported, when filings are inconsistent, or when the grantor cannot produce the records the IRS requests.

Why Cook Islands Trust Audits Are Increasing

The IRS Large Business and International Division added foreign trust information reporting to its formal compliance campaigns in 2018, signaling that the agency views this area as a persistent compliance risk. The campaign uses examinations, campus-assessed penalties for late or incomplete forms, and practitioner outreach. In 2025, the IRS released a Practice Unit on Forms 3520 and 3520-A penalties, giving examiners detailed guidance on how to calculate and impose them.

FATCA made the information flow automatic. Foreign financial institutions holding Cook Islands trust accounts now report account balances, income, and beneficial ownership directly to the IRS. The IRS cross-references these institutional reports against the grantor’s FBAR, Form 8938, and Form 3520-A. A mismatch between what the bank reports and what the taxpayer files is the single most common trigger for further examination.

What Triggers an Examination

Cook Islands trust examinations typically start from one of four sources.

FATCA cross-referencing. A discrepancy between the foreign bank’s report and the grantor’s filings—different account balances, missing income, or misidentified account holders—flags the return for review.

Form 3520 or 3520-A anomalies. Late-filed, incomplete, or internally inconsistent Forms 3520 and 3520-A attract attention. A Form 3520-A that reports trust income inconsistent with the amounts on the grantor’s Schedule E or Schedule B raises an obvious question. The IRS Large Business and International Division reviews foreign trust returns as part of its specialized compliance programs.

Income-to-asset mismatch. A grantor who reports a Cook Islands trust on the income tax return but shows minimal trust income relative to the asset values on Form 8938 may trigger examination. The IRS can estimate expected returns based on asset types and compare them to reported income.

Campaign audits. The IRS periodically runs examination campaigns focused on specific international compliance areas. Offshore trusts have been a recurring priority within the LB&I Division’s international compliance programs since the 2018 campaign launch.

What the IRS Examines

A Cook Islands trust audit focuses on three questions: Is the trust properly classified? Is all income reported? Have all required information returns been filed?

Grantor Trust Classification

The threshold issue in any Cook Islands trust examination is whether the trust is correctly classified as a foreign grantor trust under IRC sections 671 through 679. Cook Islands asset protection trusts are typically grantor trusts under Section 679, which treats a U.S. person who transfers property to a foreign trust with a U.S. beneficiary as the owner for income tax purposes.

If the IRS determines the trust is not a grantor trust—because the trust deed was drafted incorrectly, because the grantor died and no one updated the classification, or because amendments changed the trust’s terms—the tax treatment changes. Nongrantor foreign trusts are taxed as separate entities, distributions carry different tax consequences, and the throwback tax on accumulated income applies. Reclassification can produce substantial back taxes and penalties.

Income Reporting

The IRS verifies that all trust income flows through to the grantor’s personal return. For a Cook Islands grantor trust, interest, dividends, capital gains, and any other income earned within the trust structure must appear on the grantor’s Form 1040. The trust itself does not file a U.S. income tax return. The trustee files Form 3520-A as an information return, not a tax return.

The examination typically requests bank and brokerage statements for all accounts held within the trust structure, including accounts held by the Cook Islands LLC if the trust uses the standard LLC holding structure. The IRS matches these statements against the income reported on the grantor’s return.

Information Return Completeness

The IRS examines whether every required information return was filed for every year under examination. Cook Islands trust grantors must file four separate information returns: Form 3520, Form 3520-A, FBAR (FinCEN Form 114), and Form 8938.

Each form serves a different purpose, is filed with a different agency, and carries its own penalty structure. A grantor who filed Form 3520 but missed FBAR has a compliance deficiency even if every dollar of income was correctly reported on the tax return.

Penalties for Noncompliance

Information return penalties for Cook Islands trusts are among the most severe in the tax code, and they apply even when all income was correctly reported and all taxes were paid. The penalties target the failure to file information returns, not the failure to pay tax.

Form 3520. A missing or incomplete Form 3520 triggers a penalty equal to the greater of $10,000 or 35% of the transferred property value, or 5% of trust assets the grantor is treated as owning. A Cook Islands trust holding $2 million faces a potential annual penalty of $100,000.

Form 3520-A. If the foreign trustee fails to file Form 3520-A, the U.S. grantor must file a substitute return. Missing this substitute triggers a penalty equal to the greater of $10,000 or 5% of the trust assets attributable to the grantor.

FBAR. Willful failure to file FBAR carries a penalty up to the greater of 50% of the account balance or $100,000. Non-willful violations carry a $10,000 penalty per account, per year.

Form 8938. The initial penalty for missing Form 8938 is $10,000, plus $10,000 for each 30-day period noncompliance continues after IRS notice, up to $50,000. The more consequential effect: the statute of limitations on the entire income tax return never begins running until Form 8938 is filed, leaving the return open to audit indefinitely.

Continuation penalties. If the IRS sends a notice of failure to comply and the forms remain unfiled for more than 90 days, additional penalties of $10,000 per 30-day period accrue until the gross reportable amount is reached.

Accuracy-related penalties. Standard accuracy-related penalties (20% of the underpayment) and fraud penalties (75% of the underpayment) apply if the examination discovers unreported income. An additional 40% penalty under IRC § 6662(j) applies to any underpayment attributable to undisclosed foreign financial assets.

Statute of limitations. The statute of limitations for Forms 3520 and 3520-A penalties does not begin running until a complete and accurate form has been filed. If no form was ever filed, there is no statute of limitations, and the IRS can assess penalties at any time.

Responding to an Examination

The grantor’s response requires coordination between the U.S. attorney who structured the trust and the CPA or international tax counsel handling the compliance. The Cook Islands trustee will need to provide documents, but the trustee communicates through the U.S. attorney, not directly with the IRS.

Document Assembly

The IRS will request trust formation documents (the trust deed, any amendments, LLC operating agreements), all Forms 3520, 3520-A, FBAR, and Form 8938 for the examination years, and bank and brokerage statements for every account in the trust structure. Assembling these documents before the first IRS meeting demonstrates proper administration and sets the tone for the examination.

The Reasonable Cause Defense

Penalties for late or missing Forms 3520, 3520-A, and FBAR can be abated if the grantor demonstrates that the failure was due to reasonable cause and not willful neglect. Reasonable cause exists when the taxpayer exercised ordinary business care and prudence but was unable to comply on time, or when the reporting error resulted from an honest misunderstanding of fact or law.

Reliance on a qualified tax adviser can satisfy the reasonable cause standard if the grantor disclosed all pertinent facts to the adviser and relied on their guidance in good faith. The determination is fact-specific. A grantor who hired a CPA experienced in international trust reporting and followed their instructions has a stronger reasonable cause argument than one who never asked about filing requirements.

Privilege Considerations

Communications between the grantor and the U.S. attorney regarding trust formation and structure may be protected by legal privilege. Tax return preparation communications may be protected by the federally authorized tax practitioner privilege under IRC § 7525. The grantor coordinates document production with counsel to preserve applicable privileges.

Trustee Confidentiality

Cook Islands law imposes confidentiality obligations on the trustee. The trustee cannot disclose trust information directly to a foreign government. When the IRS requests information from the trustee, the request goes through the grantor and the U.S. attorney. The trustee provides documents to the grantor’s representatives, who then produce them to the IRS. This process is standard and does not create an obstruction issue as long as the grantor cooperates with document production.

Voluntary Disclosure and Remediation

Grantors who discover past compliance failures before the IRS contacts them have several remediation paths, each with different penalty structures and eligibility requirements.

Streamlined domestic offshore procedures. Available to U.S. residents who can certify that their noncompliance was non-willful, meaning negligence, inadvertence, or a good-faith misunderstanding of the law. The program imposes a 5% penalty on the highest aggregate balance of the unreported foreign financial assets during the covered years.

Streamlined foreign offshore procedures. Available to qualifying non-residents who meet the same non-willfulness certification. These procedures impose no penalty.

Delinquent international information return submission procedures (DIIRSP). Available to taxpayers who have no unreported income but missed required information returns. The grantor files the delinquent forms with a reasonable cause statement. Penalties may still be assessed, but in practice the IRS has accepted reasonable cause explanations through this channel. DIIRSP requires that the taxpayer not be under IRS examination and not have been contacted by the IRS about the delinquent returns.

Voluntary Disclosure Program. For willful violations or cases involving potential criminal exposure, the IRS Voluntary Disclosure Program provides protection from prosecution in exchange for full disclosure and civil penalties. The penalties are higher than under the other remediation programs, but the program eliminates criminal risk.

All remediation options close once the IRS initiates an examination or contacts the taxpayer about the trust. Grantors who identify unfiled returns should consult international tax counsel immediately. The CPA handles tax filing; the attorney evaluates which remediation path fits the facts.