Offshore Trusts and Non-Citizen Spouses

A U.S. citizen married to a non-citizen faces estate tax rules that do not apply to couples where both spouses hold U.S. citizenship. The unlimited marital deduction allows a U.S. citizen to leave any amount to a surviving citizen spouse free of federal estate tax. That deduction does not apply when the surviving spouse is not a U.S. citizen.

An offshore trust addresses the asset protection side of this problem while a Qualified Domestic Trust handles the estate tax deferral.

Cross-border marriages create planning problems that neither domestic asset protection nor standard estate planning solves alone. The couple’s assets may sit in multiple countries, each with its own inheritance rules. The non-citizen spouse may already hold accounts or property abroad. American expats whose financial lives already span multiple countries often find offshore trust planning a natural extension of existing arrangements. An offshore trust built into this existing international financial structure protects assets from U.S. creditors while preserving flexibility for how wealth passes between spouses and to the next generation.

The Marital Deduction Problem

Federal estate tax law allows a surviving U.S. citizen spouse to inherit an unlimited amount without triggering estate tax. This unlimited marital deduction is one of the most valuable provisions in the tax code for married couples. It does not apply when the surviving spouse is not a U.S. citizen, even if that spouse is a lawful permanent resident with a green card.

Without the marital deduction, the first spouse’s estate owes tax on assets above the federal exemption. In 2025, the exemption is $13.99 million per individual. Assets above that threshold are taxed at 40%. For couples whose combined estates exceed the exemption, the tax bill at the first death can be substantial.

The annual gift tax exclusion also changes for non-citizen spouses. The standard annual exclusion between citizen spouses is unlimited—there is no gift tax on transfers between U.S. citizen spouses regardless of amount. Transfers to a non-citizen spouse are capped at $190,000 per year. Gifts above that amount count against the lifetime estate and gift tax exemption.

How a QDOT Works and Where It Falls Short

A Qualified Domestic Trust (QDOT) is the standard solution for deferring estate tax when the surviving spouse is not a U.S. citizen. The QDOT holds assets that would otherwise be immediately taxed at the first spouse’s death. Estate tax is deferred until the surviving spouse receives distributions from the trust or dies.

QDOT requirements are strict. At least one trustee must be a U.S. citizen or U.S. corporation. If the trust holds more than $2 million, either a U.S. bank must serve as trustee or the trustee must furnish a bond or letter of credit equal to 65% of the trust’s value. The trust must be established under U.S. law and governed by U.S. courts.

A QDOT defers estate tax. It does not eliminate it. Every distribution of principal to the surviving spouse triggers estate tax at the rate that applied at the first spouse’s death. Only distributions of income are tax-free. The surviving spouse cannot simply withdraw principal without a tax consequence.

A QDOT also provides no creditor protection. Because the trust is governed by U.S. law and managed by a U.S. trustee, it is fully within the reach of U.S. courts. A creditor with a judgment against either spouse can pursue assets held in a QDOT through standard domestic enforcement procedures.

What an Offshore Trust Adds

An offshore trust solves a different problem than a QDOT. The QDOT defers estate tax. The offshore trust protects assets from creditors, provides financial privacy, and creates jurisdictional separation from the U.S. legal system. The two structures can work in parallel.

A Cook Islands trust places assets under a foreign trustee who does not answer to U.S. courts. Creditors must pursue enforcement in the Cook Islands, where they face a beyond-a-reasonable-doubt burden and a one-to-two-year statute of limitations on fraudulent transfer claims. No creditor has successfully breached a properly structured Cook Islands trust through Cook Islands litigation.

For cross-border couples, the offshore trust also addresses a practical concern. When one spouse is not a U.S. citizen, the couple’s financial life often already spans two countries. The non-citizen spouse may hold bank accounts, real property, or business interests in their home country. An offshore trust can hold the couple’s liquid assets in a single structure that protects against creditors in both the U.S. and the spouse’s country of citizenship.

Cook Islands trusts cost $20,000 to $25,000 to establish and $5,000 to $10,000 per year to maintain. These costs apply regardless of marital status or the citizenship of either spouse.

Forced Heirship and Foreign Inheritance Rules

Many countries outside the United States impose forced heirship rules that override the decedent’s stated wishes. Civil law jurisdictions across Europe, Latin America, and parts of Asia entitle children and surviving spouses to fixed shares of the estate. A will that leaves everything to one person may be partially void under local law.

Forced heirship rules apply to assets located within that country’s jurisdiction. A U.S. citizen who owns real property in France cannot simply will that property to anyone. French law reserves a portion for the children regardless of what the will says.

An offshore trust can insulate liquid assets from forced heirship claims by holding them in a jurisdiction that does not recognize forced heirship. The Cook Islands and Nevis do not apply forced heirship rules to trusts governed by their laws. Assets held in the trust pass according to the trust deed, not according to the inheritance laws of the non-citizen spouse’s home country.

Real property located in a foreign country remains subject to that country’s rules regardless of any trust structure. The offshore trust works for liquid assets—cash, securities, business interests—not for real estate held in forced heirship jurisdictions.

Multi-Country Probate

When a person dies holding assets in multiple countries, each country’s probate system may assert jurisdiction over locally held assets. The result is parallel proceedings with different timelines, different rules, and different outcomes. A surviving non-citizen spouse may need to engage attorneys in two or three countries to access jointly held assets.

An offshore trust avoids multi-country probate for the assets it holds. The trustee distributes assets according to the trust deed without court involvement. No probate filing is required in any jurisdiction. This is particularly valuable when the surviving spouse lives outside the United States and would otherwise need to engage with the U.S. probate system from abroad.

IRS Reporting for the U.S. Citizen Spouse

The U.S. citizen spouse who creates and funds the offshore trust bears all reporting obligations. The IRS treats the trust as a grantor trust under IRC Section 679 because a U.S. person funded it and U.S. beneficiaries exist. All trust income appears on the U.S. citizen’s personal return. The trust does not create a separate tax liability or defer income.

Required forms include Form 3520, reporting transactions with the foreign trust, and Form 3520-A, the trust’s annual information return. FBAR filing applies if foreign accounts connected to the trust exceed $10,000 in aggregate value. FATCA reporting on Form 8938 applies above the standard filing thresholds.

The non-citizen spouse has no U.S. reporting obligation for the trust unless that spouse is also a U.S. tax resident. A non-citizen, non-resident spouse who is named as a trust beneficiary does not file U.S. trust reporting forms solely because of the beneficiary designation.

When This Planning Makes Sense

An offshore trust paired with QDOT planning fits couples where the U.S. citizen holds substantial liquid assets, the couple faces creditor exposure in the U.S. or the non-citizen spouse’s home country, and the combined estate is large enough that the marital deduction limitation creates real tax exposure.

The planning is unnecessary if total liquid assets are below $300,000 or if neither spouse faces meaningful lawsuit risk. The planning is also premature if the non-citizen spouse is in the process of obtaining U.S. citizenship—once citizenship is granted, the unlimited marital deduction applies and the QDOT becomes unnecessary, though the asset protection rationale for the offshore trust remains.