U.S. Estate Tax and Prior Gifts: A Frequent Mistake in International Estate Planning

In European estates that include U.S. assets, exposure to the U.S. Estate Tax is often miscalculated. The issue is usually not a lack of awareness of the tax's existence, but rather a misunderstanding of how it is computed— particularly a failure to appreciate the Internal Revenue Code provisions requiring the inclusion of certain prior lifetime transfers.

This difficulty frequently arises where traditional European civil law planning strategies — notably gifts of bare ownership (nue-propriété) with a retained usufruct — were implemented years earlier.

Gifts of Bare Ownership in Europe: Effective… Under European Law

For instance, under Swiss or French civil law, gifting bare ownership while retaining usufruct is a common estate planning technique. The gift is taxed at the time of transfer based on the tax value of the bare ownership, as determined under applicable domestic rules. Upon the donor’s death, the asset no longer forms part of the donor’s estate. The usufruct terminates automatically, and full ownership passes to the bare owner without additional inheritance tax on the asset's full value.

This mechanism effectively “freezes” the taxable base at the time of the gift and reduces the estate subject to inheritance tax at death. It is widely used in European family wealth structures.

However, this civil law logic does not automatically carry over to U.S. Estate Tax purposes.

The Economic Approach of U.S. Tax Law (IRC §2036)

U.S. estate tax law is based on an economic analysis of wealth transfers. Pursuant to IRC §2036(a), property transferred during lifetime is included in the decedent’s gross estate if the decedent retained, for life, the possession, enjoyment, or the right to income from the transferred property. The retention of usufruct corresponds precisely to the retention of enjoyment and economic benefit. Accordingly, a gift of bare ownership with retained usufruct — effective in Europe to reduce the taxable estate at death — must generally be treated, for U.S. Estate Tax purposes, as an incomplete transfer.

The asset may therefore be brought back into the gross estate, regardless of the transaction's civil-law validity. This reflects a structural divergence between European property law concepts and the economic approach underlying the U.S. Estate Tax system.

Consequences for a Non-Resident Alien Holding U.S. Assets

For a non-resident alien, only U.S. situs assets are subject to U.S. Estate Tax, pursuant to IRC §§2103 and 2104. This category includes U.S. real estate and shares of U.S. corporations, even when held through a foreign financial institution. By contrast, real estate located in Europe is not directly subject to U.S. Estate Tax.

However, where an estate tax treaty applies, the credit available to significantly reduce the U.S. estate tax is generally computed based on a ratio of U.S. assets to worldwide assets. If a foreign asset gifted with retained usufruct must be reintegrated into the gross estate under IRC §2036, it will be taken into account in determining the worldwide estate used to calculate the prorated treaty credit.

Any modeling that ignores this reintegration will underestimate worldwide assets, overestimate the available treaty credit, and consequently underestimate the U.S. estate tax due on U.S. situs assets. In substantial estates, the discrepancy can be material.

The Effect of Prior Gifts on the Applicable Tax Rate (IRC §2001(b))

Beyond the inclusion rules of IRC §2036, the U.S. system operates under a unified transfer tax regime integrating Gift Tax and Estate Tax. Under IRC §2001(b), the estate tax is computed by taking into account not only the taxable estate at death, but also prior taxable lifetime gifts (“adjusted taxable gifts”).

These gifts are not taxed twice. However, they influence the marginal rate applicable to the remaining estate. Estate planning that fails to properly reconstruct the history of lifetime transfers may therefore underestimate the effective tax rate.

For a non-resident alien, IRC §2501(a)(2) limits the Gift Tax to transfers of tangible property situated in the United States. Notably, and unlike the Estate Tax, gifts of U.S. corporate shares are generally excluded from U.S. Gift Tax. This distinction is critical, but it must be analyzed carefully in each specific case.

A Frequent Error of Conceptual Transposition

The core difficulty often lies in the automatic transposition of European planning techniques into a different tax environment. In Europe, gifting bare ownership effectively reduces the estate subject to inheritance tax at death. In the United States, the retention of usufruct is precisely what may trigger reintegration into the gross estate. A strategy that produces favorable results under European law may therefore be neutral — or even ineffective — for U.S. Estate Tax purposes.

Conclusion: Reassessing Lifetime Gifts Under U.S. Estate Tax Principles

Where U.S. shares or other U.S. situs assets are involved, a careful analysis of prior lifetime transfers is essential. IRC §§2031, 2036, 2103, 2104, 2001(b), and 2102 require a complete reconstruction of the estate under U.S. tax principles. In particular, the gift of bare ownership — widely used in Europe to organize intergenerational transfers — does not necessarily remove the asset from the decedent’s taxable estate for U.S. purposes.

In any international estate planning scenario involving the United States, a specific U.S. Estate Tax analysis, including the treatment of prior gifts, is essential to avoid a significant underestimation of potential estate tax exposure at death.