Generation-Skipping Transfer (GST) Tax: How It Works in 2026

The generation-skipping transfer (GST) tax is a third federal tax — separate from estate and gift tax — that applies when wealth skips a generation on its way to grandchildren or more remote descendants. At a flat 40% rate, a $10M transfer to a grandchild could cost $4M in GST tax alone. The $15M lifetime exemption (permanent after OBBBA) is the primary tool for avoiding it, but how you allocate that exemption — and whether a dynasty trust or direct gift makes more sense — determines whether the exemption actually works.

What is the GST tax?

The GST tax was enacted as part of the Tax Reform Act of 1986 to close a loophole: wealthy families were skipping estate tax at one generation by leaving assets directly to grandchildren, bypassing their children's taxable estates entirely. Congress responded by imposing a separate 40% tax on transfers that "skip" a generation.²

The tax operates independently of — and in addition to — estate and gift tax. A transfer to a grandchild that is also a taxable gift may be subject to both gift tax and GST tax simultaneously. This is the key trap: without the GST exemption and proper planning, a single transfer can face a combined effective rate well above 40%.

Who is a "skip person"?

GST tax applies to transfers to skip persons — defined by IRC §2613 as individuals who are two or more generations below the transferor, or trusts where all current beneficiaries are skip persons. For a grandparent transferor:

• Skip persons: grandchildren, great-grandchildren, and more remote descendants. Also unrelated individuals at least 37.5 years younger than the transferor.
• Non-skip persons: children (one generation below), spouses (same generation), and other individuals less than two generations removed.

The three types of GST taxable events

GST tax is not triggered by a single event type — it can arise in three distinct ways, each with different rules for who pays and how the tax base is computed.

1. Direct skip

A direct skip is a transfer of property directly to a skip person — either as an outright gift during life, a bequest at death, or a contribution to a trust whose only beneficiaries are skip persons. Examples: writing a $1M check to your grandchild; leaving your vacation home directly to great-grandchildren in your will; funding a trust solely for grandchildren and below.

The donor or estate pays the GST tax on a direct skip. The taxable amount is the value of the property transferred.³

2. Taxable termination

A taxable termination occurs when a non-skip person's interest in a trust terminates — leaving skip persons as the only remaining beneficiaries — and no estate or gift tax applies to the transfer. The most common scenario: you fund a trust for your child's lifetime (non-skip), and at the child's death, the trust passes to grandchildren (skip persons). The termination of your child's interest is a taxable termination, and GST tax is owed at that point.

The trustee is responsible for paying GST tax on a taxable termination. The taxable amount is the value of the trust property at the time of termination.³

3. Taxable distribution

A taxable distribution is a distribution from a trust to a skip person that is not already a direct skip or taxable termination. Example: a trust for both children and grandchildren distributes income or principal to a grandchild beneficiary. Each such distribution can trigger GST tax at the time of the distribution.

The recipient (the skip-person beneficiary) is responsible for paying GST tax on a taxable distribution, though the trustee is liable if the tax isn't paid. The taxable amount is the value of the property distributed.³

The GST tax rate

The GST tax rate is a flat 40% — equal to the maximum estate and gift tax rate — imposed on the taxable amount after applying the applicable fraction and inclusion ratio (see below). Unlike income tax brackets, there is no graduated rate: the full 40% applies from the first dollar of taxable transfer.²

The $15M GST exemption

Each individual has a lifetime GST exemption equal to the federal estate and gift tax basic exclusion: $15,000,000 in 2026, permanent and inflation-indexed from 2027 (OBBBA). Married couples have a combined $30M exemption — but unlike the estate tax, there is no automatic "portability" of unused GST exemption to a surviving spouse. Each spouse must use their own exemption during their lifetime or at death.¹

How the inclusion ratio works

GST exemption is not applied as a simple deduction — it's allocated to specific transfers and trust property, producing an inclusion ratio that determines what fraction of future GST taxable events are subject to tax.

The mechanics (IRC §§2641–2642):

• Applicable fraction = GST exemption allocated ÷ value of the trust (or transferred property) at the time of allocation.
• Inclusion ratio = 1 − applicable fraction.
• GST tax on a future event = 40% × inclusion ratio × taxable amount.

If the applicable fraction equals 1 (you allocated exemption equal to the full trust value), the inclusion ratio is 0 — no GST tax ever, on any distribution or termination from that trust, regardless of how much it grows. This is the goal for a dynasty trust.

If the applicable fraction is 0 (no exemption allocated), the inclusion ratio is 1 — the full 40% applies to every taxable event.

Partial allocation produces a blended result. If you fund a $10M trust but allocate only $5M of GST exemption:

• Applicable fraction = 5 ÷ 10 = 0.50
• Inclusion ratio = 0.50
• Effective GST rate = 40% × 0.50 = 20% on every future GST taxable event from that trust

Automatic vs. affirmative allocation (IRC §2632)

Allocating GST exemption does not always require an affirmative election — the IRS built automatic allocation rules to simplify compliance. Understanding when automatic allocation applies — and when it doesn't — prevents costly mistakes.

Automatic allocation for direct skips

When a transferor makes a lifetime direct skip, GST exemption is automatically allocated to produce an inclusion ratio of zero (or as close to zero as possible given remaining exemption). A direct-skip gift to your grandchild in 2026 does not require a Form 709 election specifically allocating GST exemption — it happens by default. However, many practitioners still affirmatively allocate on Form 709 to create a clear paper trail and confirm the transfer was handled correctly.⁴

Automatic allocation for indirect skips (GST trusts)

For transfers to trusts that are not direct skips — for example, a trust for both children and grandchildren — automatic allocation applies if the trust qualifies as a GST trust under IRC §2632(c)(3)(B). In general, a trust qualifies as a GST trust if:

• No portion of the trust may be distributed to a non-skip person during the trust term, OR
• More than 25% of the trust corpus must be distributed to or may be withdrawn by a non-skip person before age 46, or upon the non-skip person's death before age 46, but the trust is nonetheless predominantly for skip persons.

In practice: a trust designed for grandchildren and below is a GST trust and receives automatic allocation. A trust designed primarily for your children (with grandchildren as contingent beneficiaries) typically does NOT receive automatic allocation, and GST exemption must be affirmatively allocated on a timely Form 709 if you want the trust to be GST-exempt.

Affirmative allocation on Form 709

For transfers where automatic allocation does not apply — or where you want precision over the amount and timing — allocate GST exemption explicitly on Form 709 (United States Gift and Generation-Skipping Transfer Tax Return). The allocation is made on Schedule D of Form 709. For testamentary transfers (at death), GST exemption allocation is reported on Form 706, Schedule R.⁴

Affirmative allocation is particularly important when:

• You want an inclusion ratio of exactly zero on a trust that may not clearly qualify for automatic allocation.
• You're allocating exemption to existing trusts that have had prior transfers without proper GST allocation.
• The trust has an unusual structure that creates ambiguity about the automatic allocation rules.

GST planning strategies for HNW families

Strategy 1: Dynasty trust (primary vehicle)

A dynasty trust is designed specifically to hold assets GST-exempt across multiple generations. Fund the trust with GST exemption equal to the full trust value (achieving a zero inclusion ratio), and all future appreciation, distributions, and terminations — for children, grandchildren, great-grandchildren, and beyond — are permanently sheltered from both estate tax and GST tax.

A married couple with $30M of GST exemption can fund a dynasty trust with up to $30M of assets, achieving a zero inclusion ratio from the start. If the trust grows to $100M over two generations, every dollar of that growth passes to descendants without estate or GST tax. The only ongoing tax inside the trust is income tax (and if structured as a grantor trust, even that falls on the grantor).

Dynasty trusts require states that permit perpetual trusts. The most common choices are South Dakota, Nevada, Delaware, Wyoming, Alaska, and Tennessee — all allow trusts to exist indefinitely without the Rule Against Perpetuities that other states impose. See our Dynasty Trust Guide for a full breakdown of best states, trustee structures, and compound-growth math.

Strategy 2: Annual exclusion gifts to grandchildren

The annual gift tax exclusion — $19,000 per recipient in 2026 ($38,000 per couple with gift splitting) — applies to direct-skip transfers to grandchildren without using any lifetime GST exemption. These annual transfers are GST-free as a matter of law, not as an exemption allocation.¹

Practical impact: a grandparent with four grandchildren can transfer $76,000/year ($19K × 4) to grandchildren — or $152,000/year per couple — without any GST tax and without touching their $15M lifetime GST exemption. Over 20 years, that's $3.04M transferred (per couple) to the grandchildren's generation, estate- and GST-tax-free, entirely separate from lifetime exemption planning.

Annual exclusion transfers to 529 plans for grandchildren also benefit from the same exclusion — and from 5-year superfunding ($95,000 per beneficiary, $190,000 per couple), which is a direct-skip transfer but uses annual exclusion treatment over the 5-year election period. See our Annual Gift Calculator to model the long-term estate impact.

Strategy 3: Direct-skip gifts using lifetime exemption

For larger transfers to grandchildren — above the annual exclusion — using lifetime GST exemption directly is the simplest approach. A $2M gift to a grandchild uses $2M of GST exemption (and $2M of gift tax exemption) but passes the full $2M without any GST tax. The gift is reported on Form 709 with explicit GST exemption allocation.

Direct lifetime gifts are often less efficient than a dynasty trust for large amounts because they skip the compounding benefit — a $5M contribution to a dynasty trust shelters all future growth from estate and GST tax, whereas a $5M direct gift to a grandchild shelters only the $5M and its growth inside the grandchild's own estate (which will eventually be taxed).

Strategy 4: Coordinated trust structures (SLAT, GRAT, IDGT)

Most advanced estate planning combines GST planning with other trust strategies. Common layers:

• SLAT funded with GST exemption: A Spousal Lifetime Access Trust can be funded with both gift tax and GST exemption, sheltering assets from the grantor's estate, providing indirect spousal access, and — if structured as a dynasty trust — protecting assets from GST tax through the grandchildren's generation as well. Not all SLATs allocate GST exemption, but many do.
• GRAT remainder to a dynasty trust: A GRAT transfers appreciation to heirs tax-free (at zero gift-tax cost). If the GRAT remainder is directed to a dynasty trust (rather than outright to heirs), the remainder uses the grantor's GST exemption at that point to lock in a zero inclusion ratio. This combination — GRAT to dynasty trust — is one of the most tax-efficient multi-generational structures available.
• IDGT installment sale: An IDGT (Intentionally Defective Grantor Trust) funded with GST exemption can purchase family business interests on an installment note. The trust grows income-tax-free (grantor pays income tax), and if the trust is dynasty-structured with a zero inclusion ratio, all growth passes to grandchildren and beyond without estate or GST tax. See our Trust Strategies Comparison.

Married couples: doubling the GST exemption

A married couple can combine their $15M GST exemptions ($30M total) through coordinated trust funding:

• Separate trusts: Each spouse funds their own dynasty trust (or SLAT/IDGT) up to their $15M exemption. The two trusts run independently.
• Joint funding but separate exemption allocation: One large trust can be funded by one spouse with $15M of GST exemption while the other contributes an additional $15M separately — though care must be taken to avoid reciprocal trust arguments on SLATs.
• Gift splitting on Form 709: A gift made by one spouse can be treated as made half by each spouse for gift tax purposes, but gift splitting does not apply to GST exemption allocation. Each spouse must allocate their own GST exemption separately. The asymmetry matters: gift splitting on a $10M transfer treats each spouse as gifting $5M (and each uses $5M of gift exemption), but the GST exemption allocation must still be separately elected by each spouse on their own Form 709.

The reverse QTIP election

When a married decedent leaves assets to a QTIP trust (see our QTIP Trust Guide), the surviving spouse is normally treated as the "transferor" for GST purposes — because the assets are included in the survivor's estate at their death (IRC §2044). This means the survivor's GST exemption applies to any generation-skipping transfers from the QTIP trust, not the original decedent's.

The reverse QTIP election (IRC §2652(a)(3)) allows the decedent's executor to elect to treat the decedent (not the surviving spouse) as the transferor for GST purposes. This allows the decedent's GST exemption to be allocated to the QTIP trust at funding — particularly valuable when:

• The decedent has more unused GST exemption than the surviving spouse.
• The QTIP trust will ultimately benefit grandchildren or more remote descendants.
• The surviving spouse's own GST exemption is better deployed on other assets.

The reverse QTIP election is made on the decedent's Form 706 and is irrevocable. It is a high-value but easily missed planning step that trust-and-estates attorneys must flag at the drafting stage.

Common GST mistakes that cost millions

1. Forgetting GST exemption is not portable. Married couples assume the surviving spouse can "pick up" unused GST exemption like they can with estate tax portability. They cannot. Couples with $20M+ estates should fund dynasty trusts at the first death to deploy the deceased spouse's GST exemption before it's lost.
2. Partial GST exemption allocation leaves a permanent blended rate. Allocating $5M of GST exemption to a $10M trust (inclusion ratio 0.50) does not become 0 when the trust grows. Every distribution and termination from that trust forever pays 40% × 0.50 = 20% GST tax. Either fully fund to zero inclusion ratio, or don't allocate and plan differently.
3. Missing the automatic allocation opt-out when you want it. A trust for your children (non-skip) that you do NOT want GST-exempt can accidentally receive automatic GST exemption allocation if it has any skip-person beneficiaries. Opting out on Form 709 is necessary to preserve that GST exemption for other uses.
4. Directing GRAT remainders outright to grandchildren without GST allocation. If a GRAT matures and the remainder passes to grandchildren, that's a direct skip at the date of GRAT expiration — GST tax applies to the remainder value unless GST exemption covers it. Routing the remainder to a dynasty trust (rather than outright) locks in the GST exemption allocation at trust funding rather than at uncertain GRAT maturity.
5. Confusing the taxable termination trigger. A trust for children with grandchildren as contingent remainder beneficiaries does not cause GST tax while children are alive. But the moment the last child's interest terminates (on their death), a taxable termination occurs on the full trust value — often a surprise decades after the trust was funded if GST exemption was never allocated.
6. Not accounting for state GST equivalents. Most states with estate taxes do not separately impose a GST equivalent (unlike federal, where estate + GST can both apply). However, a few do. Know your state's rules — domicile planning to a no-estate-tax state (Florida, Texas, Nevada) also eliminates state-level exposure on trust distributions to grandchildren.

GST exemption allocation: worked example

John and Mary ($30M net worth, both age 65) want to shelter as much as possible from estate and GST tax for their four grandchildren. Their two children have their own wealth and don't need the legacy assets.

Combined estate + GST tax savings: a $228M trust balance that passes to grandchildren and below, with zero GST tax at any generation's death, vs. a potential 40% GST rate ($91M) without the exemption structure. This is why GST planning is not optional for families with $15M+ estates.

Talk to a GST tax specialist

GST planning intersects estate tax, gift tax, grantor trust rules, trust administration, and Form 706/709 compliance in ways that generalist financial advisors rarely track. The strategies above — dynasty trust funding, GRAT-to-dynasty-trust structures, reverse QTIP elections, partial vs. full exemption allocation — each require careful coordination between your wealth advisor, trust attorney, and CPA.

If your estate is over $5M (state estate tax thresholds) or over $15M (federal), the advisors in our network focus specifically on this work. A free match is below.