The Generation-Skipping Transfer Tax: Why Dynasty Planning Has Its Own Tax

The generation-skipping transfer (GST) tax is a flat 40 percent federal tax on wealth that passes to grandchildren, later generations, or unrelated people more than 37.5 years younger, and it applies in addition to any estate or gift tax. Each person has a GST exemption of $15 million in 2026, matching the estate and gift exemption made permanent by the One Big Beautiful Bill Act, and inflation-indexed after 2026. The tax exists to close a loophole: without it, families could skip a generation and skip a round of estate tax with it. The planning consequence is that multigenerational trusts live or die on how carefully this exemption is allocated.

Why does the GST tax exist?

The estate tax is designed to apply once per generation. Before 1986, wealthy families avoided every other layer by leaving assets directly to grandchildren, or in trusts that paid income to children but passed principal to grandchildren untaxed at the children's deaths. Congress responded with the modern GST tax, which imposes a separate tax, at the highest estate tax rate, on transfers that leapfrog a generation.

The rate is a flat 40 percent in 2026, equal to the top estate and gift tax rate (Congressional Research Service overview of the GSTT). It is not graduated. Every dollar of a generation-skipping transfer above your available exemption is taxed at the full rate, potentially on top of the 40 percent estate or gift tax on the same dollars.

Who counts as a "skip person"?

A skip person is anyone two or more generations below you: grandchildren, great-grandchildren, and so on. For people outside your family, generation is measured by age, and anyone more than 37.5 years younger than you is treated as a skip person. A trust can also be a skip person if all of its beneficial interests are held by skip persons.

One humane exception matters often: the predeceased parent rule. If your child dies before you, that child's children move up a generation. A bequest to a grandchild whose parent (your child) has already died is not a generation-skipping transfer at all.

What kinds of transfers trigger the tax?

The statute taxes three events:

• Direct skips: an outright gift or bequest to a skip person, such as $1 million left directly to a grandchild. Estate or gift tax applies, and GST tax applies on top, to the extent exemption is not allocated.
• Taxable terminations: a trust interest ends and only skip persons remain. The classic case is a trust paying income to your child for life, then passing to grandchildren at the child's death; the termination is the taxable moment.
• Taxable distributions: a trust with mixed generations distributes assets to a skip person, such as a discretionary payment from a family trust to a grandchild.

Two everyday carve-outs keep ordinary generosity out of the system. Direct payments of a grandchild's tuition or medical bills to the provider are GST-free without limit, mirroring the gift tax rule. Annual exclusion gifts ($19,000 per recipient in 2026 per IRS inflation adjustments) made outright to a grandchild are also GST-free; the same gift made to a trust qualifies only if the trust meets strict requirements under Section 2642(c), a distinction that catches many families by surprise.

How does the GST exemption work, and what is an inclusion ratio?

Each person can allocate $15 million of GST exemption (2026) against transfers or trusts. A trust to which exemption is fully allocated has an "inclusion ratio" of zero: nothing the trust ever distributes or terminates is subject to GST tax, no matter how large it grows. A trust with no exemption allocated has an inclusion ratio of one, fully exposed at 40 percent.

The arithmetic rewards early allocation. As a hypothetical, a grandmother funds a dynasty trust with $5 million in 2026 and allocates $5 million of GST exemption, making the trust fully exempt. If the trust grows at 7 percent for 40 years it holds roughly $75 million, all of it permanently outside the GST and estate tax systems. Had she instead left $75 million to the same trust at her death 40 years later, sheltering it would consume her entire exemption and more, with the excess taxed at 40 percent. Exemption allocated to a dollar today shelters everything that dollar becomes.

Two cautions accompany this. First, partially exempt trusts (inclusion ratios between zero and one) are an administrative headache; planners prefer to keep fully exempt and non-exempt assets in separate trusts. Second, unlike the estate exemption, the GST exemption is not portable between spouses; a deceased spouse's unused GST exemption is lost, which argues for deliberate use during life or at the first death.

What are the allocation traps?

Congress built automatic allocation rules into the law so that families would not lose the exemption by oversight: exemption allocates automatically to direct skips and to lifetime transfers to "GST trusts" as defined in the statute. The definition, however, is famously convoluted, and the automatic rules misfire in both directions.

They under-allocate when a trust that the family intends for grandchildren fails the statutory definition, leaving the trust exposed despite everyone's assumptions. They over-allocate when exemption automatically attaches to a trust that will likely never benefit skip persons, such as many GRATs or trusts expected to pay out entirely to children, wasting exemption that a dynasty trust needed. Transfers to GRATs carry an additional timing rule: during the period the trust would be pulled back into your estate (the ETIP), exemption generally cannot be allocated effectively at all.

The remedy is unglamorous but reliable: file gift tax returns (Form 709) for trust transfers and make explicit elections, either electing into allocation for trusts you want exempt or electing out for trusts you do not. Allocation decisions should be reviewed whenever a trust is funded, not reconstructed years later when a distribution to a grandchild forces the question.

Key numbers for 2026

Frequently asked questions

Is the GST tax in addition to the estate tax?Yes. A bequest to a grandchild above both exemptions can be hit by the 40 percent estate tax and a 40 percent GST tax, which is why unplanned generation-skipping transfers are among the most expensive moves in the tax code.

Are gifts to my grandchildren during my lifetime taxed?Outright gifts within the $19,000 annual exclusion, plus tuition and medical bills paid directly to providers, are free of both gift and GST tax. Larger gifts use your lifetime exemptions, and gifts to trusts need careful GST treatment.

Does my will or trust automatically handle GST exemption?No. Allocation happens on gift and estate tax returns, partly through automatic rules that often misfire. Explicit elections on Form 709 are the reliable approach.

My child is deceased; do gifts to that child's children get penalized?No. Under the predeceased parent rule, those grandchildren move up a generation and are not skip persons for your transfers.

Is the GST exemption portable to my surviving spouse like the estate exemption?No. Unused GST exemption dies with the first spouse, which is a key reason couples plan GST allocation deliberately rather than defaulting everything to the survivor.

How long can a GST-exempt trust last?As long as state law allows. States such as South Dakota, Delaware, and Wisconsin permit trusts of effectively unlimited duration, which is what makes fully exempt dynasty trusts so powerful.