What Is the Estate Tax Exemption for a Noncitizen Spouse?

When a U.S. citizen dies leaving assets to a spouse who is not a U.S. citizen, the unlimited marital deduction that normally lets spouses inherit tax-free is gone. The estate tax exemption for a non-citizen spouse is the same $15 million (in 2026) that applies to any beneficiary, and everything above that faces federal estate tax at rates up to 40% unless the assets pass through a Qualified Domestic Trust (QDOT) or the surviving spouse becomes a U.S. citizen before the estate tax return is filed.¹

Why the Marital Deduction Doesn’t Apply

Federal law is blunt: if the surviving spouse is not a U.S. citizen at the time of the decedent’s death, no marital deduction is allowed.² Permanent residency doesn’t help. A green card holder who has lived in the country for decades is treated the same as someone who has never set foot in it. The reasoning is that a non-citizen surviving spouse could leave the United States with the inherited assets, and the IRS would have no way to collect estate tax when that second spouse eventually dies.

The decedent’s own exemption still functions normally. For 2026, up to $15 million in assets can pass to anyone, including a non-citizen spouse, without triggering estate tax.¹ The problem starts above that line. At a 40% top rate, an estate worth $25 million passing to a non-citizen spouse would owe roughly $4 million in estate tax with no planning in place. That same transfer between two citizens would owe nothing.

Portability compounds the disadvantage. The ability to carry a deceased spouse’s unused exemption to the survivor, which effectively doubles the shelter to $30 million for citizen couples in 2026, is generally unavailable when the surviving spouse is not a U.S. citizen.³ Using the first spouse’s exemption fully at death, rather than saving it, matters more here than in a citizen couple.

The Qualified Domestic Trust

The only route to claim the marital deduction for property passing to a non-citizen spouse is to route it through a QDOT.² The QDOT does not eliminate the tax. It defers it. The assets sit inside a trust the IRS can monitor, and the deferred estate tax comes due when principal is distributed or the surviving spouse dies.

Trustee and Distribution Requirements

At least one trustee must be a U.S. citizen or a domestic corporation. That U.S. trustee is personally responsible for withholding and paying the deferred estate tax whenever principal leaves the trust.⁴ The trust document itself must give the trustee the right to withhold that tax before any principal reaches the surviving spouse. Without that power written in, the trust doesn’t qualify.

The surviving spouse must receive all trust income, paid at least annually. Income distributions are not taxable events under the QDOT rules. Only distributions of principal trigger the deferred estate tax.⁵

Security Rules for Larger Trusts

QDOTs holding more than $2 million (valued at the decedent’s date of death, before debts on those assets) must satisfy one of three added security conditions:

At least one trustee is a U.S. bank or other domestic institution.
The U.S. trustee posts a bond to the IRS equal to 65% of the fair market value of the trust property.
A qualified financial institution issues an irrevocable letter of credit for the same 65% amount.

For QDOTs valued at $2 million or less, the trust must include an agreement to file an annual statement reporting the trust assets and their location. If the trust’s value later crosses the $2 million threshold, the stricter security conditions kick in.

Making the Election

Meeting the structural requirements isn’t enough on its own. The deceased spouse’s executor must make an irrevocable election on Form 706, the federal estate tax return, to treat the trust as a QDOT, and the election must be filed by the return’s due date including extensions.² Property can also be transferred or irrevocably assigned to the trust on or before that deadline. No partial elections are allowed, and the executor cannot revoke it once made. Missing the deadline means the estate tax comes due immediately with no second chance.

When the Deferred Tax Comes Due

Three events pull the trigger on the deferred tax. The first is a distribution of principal to the surviving spouse. Any distribution that is not income triggers estate tax on the amount distributed.⁵ The second is the death of the surviving spouse, at which point the remaining principal is taxed at its value on that date. The third is the trust ceasing to qualify, for example if the U.S. trustee resigns without replacement or the required security lapses. When that happens, the entire remaining principal becomes immediately taxable.

The Hardship Exception

Not every principal distribution triggers tax. Distributions on account of hardship are exempt, but the definition is narrow. The need must be immediate and substantial and relate to the surviving spouse’s health, maintenance, education, or support, or the same needs of anyone the spouse is legally obligated to support.⁶

The spouse also has to show the funds cannot be obtained from other reasonably available sources. Publicly traded stocks and certificates of deposit count as available sources that disqualify the claim. Closely held business interests, real estate, and tangible personal property do not, so the spouse doesn’t have to liquidate a family business or sell a home to reach the hardship exception.⁶

How Much Tax Actually Applies

The tax on a QDOT distribution isn’t calculated at current rates. It uses the tax rates and unified credit from the first deceased spouse’s estate, as if the marital deduction had never been claimed.⁵ Each taxable distribution is stacked on top of all previous taxable distributions from the trust, taxed at the original decedent’s marginal rate, with credit for taxes already paid. Spreading distributions across many years doesn’t reduce the rate.

Jointly Owned Property: A Common Trap

Joint ownership works differently when the surviving spouse isn’t a citizen. Normally, when citizen spouses hold property as joint tenants or tenants by the entirety, only half the value is included in the first spouse’s estate. That 50/50 rule does not apply to a non-citizen surviving spouse.⁷

Instead, the IRS presumes the entire value of jointly held property belongs to the decedent’s estate. The executor can reduce that amount only by proving, with records, how much of the original purchase price the surviving spouse actually contributed. If the couple bought a home for $800,000 using a joint account into which the decedent contributed 60% and the surviving spouse 40%, then 60% of the property’s current value is included in the estate.⁸ Only the portion included in the decedent’s gross estate can be transferred to a QDOT.⁷

The practical implication is documentation. Keep clear records of each spouse’s financial contributions to jointly held assets, including bank statements, deposit records, and proof of separate earnings used for purchases. Without a paper trail, the IRS will include 100% of the asset’s value in the decedent’s estate.

Ways to Reduce What Passes Through a QDOT

A QDOT works, but it locks the surviving spouse into ongoing compliance, a U.S. trustee, and distribution restrictions for life. Several strategies shrink the amount that needs to sit in a QDOT, or eliminate the need for one.

Becoming a U.S. Citizen

The cleanest solution is for the surviving spouse to become a naturalized citizen before the deceased spouse’s Form 706 is filed. If that happens, the unlimited marital deduction applies as though the citizenship limitation never existed, provided the surviving spouse was a U.S. resident at all times between the decedent’s death and the naturalization date.² A spouse who leaves the country for an extended stretch during that window won’t qualify.

If citizenship comes after a QDOT is already in place, the trust can escape the distribution tax going forward too, but conditions apply. The spouse must have been a U.S. resident continuously after the decedent’s death, and either no taxable distributions were made from the QDOT before citizenship, or the spouse elects to treat prior taxable distributions as taxable gifts for their own gift and estate tax purposes.⁹ The residency requirement is what trips up spouses who split time between the U.S. and their home country.

Annual Gifting During Life

The annual gift tax exclusion for transfers to a non-citizen spouse is far larger than the standard exclusion. For 2026, a citizen spouse can give up to $194,000 per year to a non-citizen spouse without gift tax, compared to $19,000 for gifts to any other individual.¹⁰ Starting a gifting program years before death moves substantial wealth, and all its future appreciation, out of the taxable estate. Ten years of runway is close to $2 million transferred with no QDOT overhead at all.

Life Insurance Held in Trust

Life insurance proceeds are not subject to estate tax if the deceased didn’t own the policy. An irrevocable life insurance trust owns the policy instead, keeping the death benefit outside the taxable estate. For non-citizen spouse planning, this creates liquid, tax-free cash the surviving spouse can access without QDOT restrictions. The same proceeds can also fund the estate tax bill on assets that do pass through a QDOT, so illiquid property like real estate or a business doesn’t have to be sold to pay the tax.

Treaty Benefits

The United States has estate tax treaties with a handful of countries that can change the standard rules. The U.S.–Canada treaty, for example, provides a nonrefundable marital credit against U.S. estate tax for certain property passing to a surviving spouse who is a U.S. or Canadian resident.¹¹ Claiming that credit requires the executor to waive the domestic marital deduction, so it’s an either/or decision. Other countries with U.S. estate tax treaties include Germany, the United Kingdom, Japan, and France. Benefits vary by treaty, and deciding whether a treaty credit or a QDOT produces a better result requires running the numbers for the specific estate.

If the surviving spouse becomes a U.S. citizen before the Form 706 filing deadline, portability can also be elected on that return.² That narrow window is another reason the timing of naturalization matters so much in this kind of planning.

1
Internal Revenue Service. What’s New — Estate and Gift Tax
2
Office of the Law Revision Counsel. 26 USC 2056 – Bequests, Etc., to Surviving Spouse
3
Internal Revenue Service. Frequently Asked Questions on Estate Taxes for Nonresidents Not Citizens of the United States
4
Office of the Law Revision Counsel. 26 USC 2056A – Qualified Domestic Trust
5
Internal Revenue Service. Instructions for Form 706-QDT
6
eCFR. 26 CFR 20.2056A-5 – Imposition of Section 2056A Estate Tax
7
eCFR. 26 CFR 20.2056A-8 – Special Rules for Joint Property
8
eCFR. 26 CFR 20.2056A-8 – Special Rules for Joint Property
9
Office of the Law Revision Counsel. 26 USC 2056A – Qualified Domestic Trust
10
Internal Revenue Service. Frequently Asked Questions on Gift Taxes for Nonresidents Not Citizens of the United States
11
Internal Revenue Service. 4.25.4 International Estate and Gift Tax Examinations