Why Did the Permanent Exemption Make Estate Planning Harder?

Most family office principals who completed aggressive gifting strategies in 2023 and 2024 believe their work is done. Congress made the $15 million exemption permanent. The sunset cliff is gone. Time to move on.

That assumption is costing families real money right now.

The One Big Beautiful Bill Act (OBBBA), signed July 4, 2025, eliminated one planning risk while quietly creating three others. The same law that removed the exemption sunset also introduced a double-taxation trap inside existing irrevocable trusts, activated formula clauses that are misdirecting inheritances in probate courts today, and penalized principals who over-transferred assets before the sunset arrived. Most family office operators do not know any of this has happened.

This post explains what changed, who is most exposed, and what the most effective tax attorneys are doing about it right now.

The Problem: Permanence Did Not Mean Stability

Here is what the OBBBA actually produced for family offices managing $500M–$2B in assets.

A double-tax embedded inside every distributing trust. The Joint Committee on Taxation's May 2026 Bluebook (Footnote 102) confirmed that the OBBBA's new Section 68 limitation applies to trusts and estates - reducing the deduction a trust can take when it distributes income to a beneficiary. The result: the trust pays tax on income the beneficiary also reports. On a $1 million distribution, this disallowance produces approximately $54,000 of residual taxable income at the trust level, generating roughly $20,000 in incremental trust-level income tax. Non-grantor trusts hit the 37% federal bracket at just $16,000 of taxable income in 2026 - meaning this problem applies to virtually every substantive irrevocable trust in existence.

Formula clauses routing assets to the wrong place. Millions of estate plans contain language that funds a credit shelter (bypass) trust with "the maximum amount that can pass free of federal estate tax." When that language was drafted - anywhere from 2001 to early 2026 - the exemption was $1 million to $13.99 million. At $15 million, that same clause can route an entire estate to the bypass trust and leave the surviving spouse with zero outright inheritance. The step-up in income tax basis that heirs would have received under IRC §1014(a) disappears with it. Katten LLP flagged this in November 2025. By April 2026, Ginsberg Shulman was more direct: "This is happening in Florida right now."

Over-transferred IDGTs with no estate tax offset. Principals who moved assets aggressively into Intentionally Defective Grantor Trusts (IDGTs) - trusts designed to remove assets from the taxable estate while the grantor pays income taxes - to lock in the pre-sunset exemption may have depleted their estates past the point where the strategy makes financial sense. Bernstein Private Wealth Management modeled a $30M estate in June 2026 and found that IDGT overplanning cost that family $1.2 million in after-tax wealth, because the heirs lost the capital gains step-up without generating the estate tax savings that justified the transfer. At $500M+ of assets, the scale of that calculation is an order of magnitude larger.

Why This Is Still Happening

The OBBBA was signed thirteen months ago. Why are most family offices still exposed?

The answer is structural, not technical. In the $500M–$2B segment, estate plans get reviewed when principals initiate contact - around a liquidity event, a family transition, or a tax filing. Legislative change alone does not trigger a review. The OBBBA passed on July 4th of last year. No triggering event. No review.

The Section 68 double-taxation issue is an additional layer of obscurity. It did not appear in a Revenue Ruling or IRS Notice. It surfaced in a footnote of a technical Bluebook published by the Joint Committee on Taxation in May 2026 - a document that most trust officers and family office COOs have never seen. ACTEC formally told Treasury in November 2025 that applying Section 68 to trust distributions "may result in double taxation" and requested either a technical correction or IRS guidance. That guidance has not yet arrived. Until it does, fiduciaries who distribute without accounting for the haircut are exposed to under-withholding claims and beneficiary disputes.

On the governance side, UBS's 2026 Global Family Office Report found that fewer than half of family offices have formal governance frameworks with board-level oversight. That gap is why these risks accumulate without detection. There is no systematic protocol that connects a change in tax law to a document review, a trustee memo, or a distribution modeling exercise.

What One Family Office Did About It

David Hargrove's $750M single-family office discovered the architecture problem the hard way during the 2024 filing season. The office managed interests across 31 entities. Three limited partnerships showed conflicting ownership percentages between the internal cap table, the outside tax attorney's entity map, and the Delaware state filings. Each had been updated in one spreadsheet but not the others.

Fixing it required amended K-1s for 11 partners across four entities, a cost basis review for two trust structures, and a 47-day filing delay for six entities - generating $28,000 in late-filing penalties under IRC §6698. The error started with one ownership transfer.

Hargrove's response was not a new software platform. It was a governance decision: one entity register, one system of record, and a rule that every tax preparation begins from an export of that register - not a separately maintained file. The first full filing season using that system produced zero ownership discrepancies and shortened preparation by three weeks.

He applied the same logic to his post-OBBBA estate plan. Every irrevocable trust mapped to its risk category. Every formula clause flagged. Every year-end distribution decision reviewed against a Section 68 model before authorization.

That is what proactive looks like in 2026.

What the Most Effective Tax Attorneys Are Doing Now

Running a post-OBBBA estate plan triage audit.

The first step is a formula clause scan - pulling every estate planning document and identifying any language that ties trust funding to "the applicable exclusion amount" or "the maximum amount that can pass free of federal estate tax" without a fixed-dollar cap. Documents drafted between 2001 and 2018 are the highest-risk cohort.

The audit then maps each irrevocable trust to one of four risk categories: formula clause mis-triggering, Section 68 double-taxation exposure, IDGT overplanning with a forfeited step-up, or GST exemption allocation gaps. Deloitte Tax's analysis in The Tax Adviser (March 2026) identified the credit shelter trust formula review as the first post-OBBBA planning imperative - noting that for estates below $30M, the primary risk has shifted entirely from estate tax to income tax and basis preservation.

This is a 60 to 90-day project. It requires the principal, the estate attorney, the CPA, and the trust officer in the same planning conversation - because the interaction effects between formula clause risk, Section 68 exposure, and IDGT overplanning cannot be evaluated in isolation.

Modeling Section 68 before every year-end distribution.

Every irrevocable non-grantor trust with 2026 distributions needs a tax projection that accounts for the JCT's Bluebook interpretation before the trustee authorizes any payment. The model quantifies the Section 68 disallowance on distributable net income (DNI) deductions - the haircut on what the trust can deduct when it pays income to beneficiaries - and determines whether to retain more income in the trust, reduce the distribution, or exercise a swap power to shift the structure.

The modeling step is also a fiduciary documentation step. Trustees who distribute in 2026 without a documented analysis of the Section 68 risk face potential under-withholding claims and beneficiary disputes after filing. PKF O'Connor Davies explicitly advised in June 2026 that fiduciaries "should closely monitor developments and revisit trust tax projections, charitable planning strategies, and beneficiary distribution assumptions" until IRS guidance or a technical correction arrives. The only defensible position right now is a documented one.

Unifying cross-border documentation into a single master record.

For the 57% of family offices with at least one family member residing outside the primary jurisdiction - per the 2025 Campden Wealth / AlTi Tiedemann Global Family Office Operational Excellence Report - cross-border reporting is not optional, and fragmented documentation is no longer just a compliance gap. It is an active enforcement trigger.

In 2026, regulators compare FATCA, CRS 3.0, and CARF (Crypto-Asset Reporting Framework) filings across jurisdictions using unified data schemas. CRS 3.0's XML Schema v3.0 was specifically designed to mirror CARF's data structure - so when the definition of "controlling person" in a family office's FATCA filing does not match the CRS self-certification, that inconsistency is visible to regulators in every participating jurisdiction simultaneously. Foodman PA confirmed in December 2025: these three frameworks "no longer function as isolated reporting tracks. They operate as an integrated system."

The fix is one master entity record - one definition of controlling person, one ownership register, one classification of account type - that propagates across every reporting framework. Any change to trust structure, ownership, or beneficiary residence triggers a synchronized update across all filings within 30 days.

Your Next 30 Days

The permanence of the $15M exemption did not simplify this landscape. It transferred the primary risk from estate tax to income tax - from a future legislative clawback to a present, silent accumulation of misfiring structures.

The offices that protect their capital in 2026 are not the ones with the most advanced planning. They are the ones whose advisors identified the new risks before a death event made them irreversible.

In the next 30 days: Pull every estate planning document in your portfolio and search for the phrase "the maximum amount that can pass free of federal estate tax" or "the applicable exclusion amount" without a fixed-dollar cap. If you find it, you have found your highest-priority exposure. Call your estate attorney before your next quarterly trustee meeting.

In the next 60 days: Have your CPA model the Section 68 disallowance across every distributing non-grantor trust. Document that the trustee reviewed the analysis before year-end distributions are authorized. That documentation is your fiduciary protection regardless of how the IRS ultimately resolves the guidance question.

In the next 90 days: Map your cross-border reporting obligations - FATCA, CRS, CARF, AML - and identify where the definitions of ownership and control diverge. Build the single master record. Implement the trigger protocol.

The JCT's Bluebook is the operative standard today. IRS guidance has not arrived. ACTEC and the NYSBA are waiting for a technical correction that may not come before year-end. The window to model, document, and act is open. It will not stay that way.