The federal estate and gift tax exemption is scheduled to drop by roughly half on January 1, 2026 unless Congress acts. Funding either a dynasty trust or SLAT before that date locks in today's higher exemption permanently, even if the law changes after the fact.
Dynasty Trust
A dynasty trust is designed to hold wealth for 100 to 1,000 years depending on situs state, with South Dakota, Nevada, and Delaware being the top choices because they have abolished the rule against perpetuities entirely. You fund it with up to the current federal lifetime exemption (roughly $13.6 million per person as of 2024), allocate GST exemption at funding, and the trust passes from generation to generation without triggering estate tax at each death. Neither the grantor nor the spouse has automatic access to principal, which is the core tradeoff versus a SLAT. Setup through a South Dakota trust company runs approximately $5,000 to $15,000 in legal fees plus ongoing trustee fees of 0.25% to 0.75% of assets annually. This structure fits families who have already secured retirement assets outside the trust and want maximum multigenerational compounding. For a direct comparison of how dynasty trusts stack up against simpler irrevocable structures, see Dynasty Trust vs Revocable Trust: Which One Actually Protects Wealth?
Spousal Lifetime Access Trust (SLAT)
A SLAT is an irrevocable trust where the grantor funds it and names their spouse as a discretionary beneficiary, giving the couple indirect access to the assets through the spouse during the marriage. This solves the access problem that makes pure dynasty trusts feel uncomfortable for couples who are not yet fully financially independent from their wealth. The tradeoff is real: if the marriage ends through divorce or the spouse dies, that access disappears entirely, and the grantor cannot be added back as a beneficiary without collapsing the tax benefits. Funding typically uses the same federal exemption amounts as a dynasty trust, and SLATs are most commonly sited in states like Nevada or South Dakota to pick up creditor protection benefits. Legal setup runs roughly $3,000 to $8,000, slightly less than a dynasty trust because the drafting complexity is lower. SLATs work best for couples in their 50s or early 60s who want to lock in current high exemption amounts before they sunset in 2026 but are not comfortable leaving all liquidity inside a trust the spouse cannot touch.
GST Exemption Allocation and Tax Mechanics
Both structures rely on the generation-skipping transfer tax (GST) exemption to pass assets to grandchildren and beyond without a 40% GST tax layered on top of estate tax. The difference is that a dynasty trust is almost always fully GST-exempt from day one, whereas a SLAT sometimes is and sometimes is not, depending on whether the drafting attorney allocates GST exemption at funding. A SLAT that skips GST exemption allocation works fine for passing assets to children but hits a 40% GST tax wall the moment you try to benefit grandchildren or later generations. If your goal is truly multigenerational transfer, the dynasty trust wins on tax mechanics because the GST shield is built into its structural DNA, not an afterthought. Neither structure avoids gift tax at funding; both consume lifetime exemption when assets go in, which is exactly the point before the exemption potentially halves in 2026.
Reciprocal Trust Risk and the Dual-SLAT Problem
Many married couples are pitched on creating two SLATs simultaneously, one where each spouse is the grantor of the other's trust, so both have indirect access through their beneficiary spouse. The IRS reciprocal trust doctrine can collapse this arrangement if the trusts are substantially similar and created close together in time, treating each grantor as if they retained an interest in their own trust and pulling the assets back into the taxable estate. To manage this risk, attorneys stagger the funding dates, use different asset classes for each trust, and vary the distribution standards. A dynasty trust avoids this specific risk because neither spouse is a beneficiary, so there is no reciprocal access to challenge. Families drawn to the dual-SLAT approach should budget for additional drafting complexity and ongoing legal review, typically adding $2,000 to $5,000 to total setup cost.
Things people ask first.
Can a dynasty trust also give my spouse access like a SLAT does?
Yes, a dynasty trust can include the spouse as a discretionary beneficiary, which functionally makes it a SLAT with a very long duration. The tradeoff is that naming the spouse adds reciprocal trust risk and requires more careful drafting. Many estate attorneys treat these as a hybrid rather than two fully separate structures.
Which states are best for setting up a dynasty trust?
South Dakota, Nevada, and Delaware are the three most common choices. South Dakota has no state income tax on trust income retained inside the trust, strong asset protection statutes, and no limit on trust duration. Nevada is close behind on all three metrics and allows a two-year fraudulent transfer lookback period rather than the typical four years.
What happens to a SLAT if my spouse dies?
The assets stay in the trust and continue for the benefit of whoever is named as the remainder beneficiary, typically children or further descendants. But the spousal access is gone permanently, and the grantor cannot be added as a substitute beneficiary without triggering inclusion back into their estate.
Do I need a trust company as trustee for a dynasty trust?
For a South Dakota or Nevada dynasty trust intended to last beyond a single generation, yes, a licensed trust company is effectively required because individual trustees die and institutional continuity is part of the deal. Annual fees typically run 0.25% to 0.75% of assets under management, with minimums often around $3,000 to $5,000 per year.
Can I put life insurance inside either of these trusts?
Yes, both structures can hold life insurance policies, and doing so is a common strategy. An irrevocable life insurance trust (ILIT) is essentially a specialized version of this concept. Placing a policy inside a dynasty trust combines tax-free death benefit compounding with multigenerational GST-exempt transfer, which is one of the more powerful combinations in estate planning.
What is the gift tax cost to fund a SLAT or dynasty trust?
Funding either trust is a completed gift that consumes your federal lifetime exemption dollar for dollar. At current 2024 levels that is up to $13.61 million per person with no gift tax owed until you exceed that amount. Assets transferred into the trust, plus all future appreciation, are permanently outside your taxable estate.
Ready to choose the right trust structure before the 2026 exemption cliff hits?
The Offshore Playbook covers dynasty trust siting, SLAT drafting pitfalls, GST exemption allocation, and how to layer life insurance inside both structures for maximum tax-free compounding. Get the exact playbook used to structure multigenerational wealth correctly the first time.
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