Firms for Maximizing QSBS Stacking: What Sets Capable Advisors Apart

Most founders with qualifying stock know that QSBS offers a federal tax exclusion. But few realize the basic exclusion is just the starting point. Through a strategy called QSBS stacking, founders facing exits north of the $20 million range can multiply their total tax-free gains well beyond a single per-person cap. The difference can be tens of millions of dollars in additional exclusions, but only if the right firm is executing the strategy.

The catch? Most firms talk about QSBS stacking. Far fewer can actually execute it. This article breaks down what QSBS stacking requires, why it trips up so many advisors, and what separates firms that can deliver on this strategy from those that cannot.

Under Section 1202 of the tax code, each taxpayer can exclude gain from a qualifying stock sale up to a per-issuer cap: the greater of a flat dollar amount or 10 times the adjusted basis of the stock sold. For stock acquired on or before July 4, 2025, the flat amount is $10 million.

The One Big Beautiful Bill Act (OBBBA), signed into law on July 4, 2025, raised the flat amount to $15 million for stock acquired after that date, indexed for inflation beginning in 2027. The cap applies per taxpayer, per issuer. The key word is “per person.”

One caution before the math: spouses filing jointly are generally treated as one taxpayer for the per-issuer cap. Stacking multiplies exclusions through genuinely separate taxpayers, such as properly structured non-grantor trusts, not through a joint return. On a $50 million exit, a founder holding all shares personally excludes $10 million (assuming pre-OBBBA stock, which describes virtually every founder exiting in the next few years) and pays federal long-term capital gains tax of 23.8% (20% plus the 3.8% Net Investment Income Tax) on the remaining $40 million. That is roughly $9.5 million in federal tax on gain that could have been excluded. QSBS stacking changes this calculation. The strategy transfers portions of QSBS to multiple qualified holders well before any sale. Each holder gets its own per-taxpayer, per-issuer exclusion cap.

On a $50 million exit, the difference between those two rows is roughly $4.8 million in federal tax savings, before any state tax benefit. That figure alone illustrates why founders need a firm that can actually execute this, not just explain it. For stock acquired after July 4, 2025, the math improves further: each holder’s cap rises to $15 million, though that stock cannot reach the full 100% exclusion until it has been held at least five years, meaning July 2030 at the earliest.

A related but distinct strategy, QSBS packing, focuses on increasing the basis of the stock to raise the 10 times basis side of the cap formula. Packing can be combined with stacking, but it is a separate strategy with its own mechanics and deserves its own analysis.

QSBS stacking sounds straightforward on paper. In practice, it requires coordination across tax law, trust and estate planning, and state-level compliance. Most advisors are strong in one of these areas. Very few are equipped to manage all three at once. A CPA may understand Section 1202 well. A wealth manager may know that the basic exclusion exists. An estate attorney may know how to form a trust. But QSBS stacking requires all three disciplines working together under tight timing constraints, with each piece carefully integrated. Most general advisors do not engage founders early enough to make this work. By the time they get involved, often with a deal already in motion, the window for executing a stacking strategy may have already closed.

The gap between knowing about QSBS stacking and executing it correctly is significant. Founders who do not probe this gap often discover it after the LOI is signed, which is too late.

A firm that can maximize QSBS stacking needs working knowledge of three specific tools, when to use each one, and how they interact.

Gifting Shares to Family Members

Qualified QSBS shares can be gifted to family members. When structured correctly, each recipient holds their own QSBS position with their own per-person exclusion cap. This is not as simple as a share transfer. Under Section 1202(h), a recipient of gifted QSBS steps into the donor’s shoes: the stock keeps its QSBS status, the donor’s holding period tacks to the recipient, and the recipient takes the donor’s basis.

Because basis carries over, the 10 times basis side of the cap is based on the founder’s original basis, which is usually near zero, so gifted QSBS typically relies on the flat per-taxpayer cap. Each gift consumes lifetime gift and estate exemption and should be reported on a timely filed gift tax return. And the gift must happen well before any sale is practically certain.

Irrevocable Non-Grantor Trusts

Each properly structured non-grantor trust is treated as a separate taxpayer under Section 1202. That means each trust gets its own exclusion cap. This is where firm expertise matters most. The trust must be irrevocable and structured as a non-grantor trust, meaning the founder cannot retain the powers or benefits that would cause trust income to be taxed back to the founder under the grantor trust rules.

This is a common failure point: a grantor trust is not a separate taxpayer and adds no additional exclusion, and even a standard spousal lifetime access trust (SLAT) is typically a grantor trust unless deliberately drafted otherwise. Trust domicile also matters.

For California founders specifically, where the state does not conform to the federal QSBS exclusion and applies a top 13.3% rate on the full gain, a properly structured non-grantor trust sited in a state like Nevada can remove that portion of the gain from California tax. But situs alone is not enough. California taxes non-grantor trust income based on the residence of the trust’s fiduciaries and its non-contingent beneficiaries (Cal. Rev. & Tax. Code Section 17742), so a Nevada trust with a California trustee or a California resident non-contingent beneficiary can still face California tax. Trustee selection and beneficiary design must be paired with situs, and the trust must be structured and funded early enough.

Section 1045 Rollover

When stacking does not cover the full taxable gain, a Section 1045 rollover lets founders defer tax by reinvesting proceeds into stock of another qualified small business. The original QSBS must have been held more than six months, replacement QSBS must be purchased within 60 days of the sale, and both the sold stock and the replacement stock must independently meet the QSBS requirements.

The deferred gain reduces the basis of the replacement stock, so this is a deferral, not an exclusion, and rolling over pre-OBBBA stock does not convert it to the post-OBBBA $15 million cap or tiered exclusions.

Each mechanism carries its own compliance requirements. A firm that can execute one does not automatically have the capability to handle the others.

Stacking is not free, but the cost is usually exemption, not cash. Every share moved to a trust or family member is a completed gift that draws down the founder’s lifetime gift and estate exemption, which is $15 million per individual in 2026 and $30 million combined for a married couple.

No gift tax is actually paid unless cumulative lifetime gifts exceed those thresholds; below them, the gift simply consumes exemption. Each transfer should be reported on a timely filed gift tax return with adequate disclosure, often supported by a qualified appraisal. Transferring early, while equity value is still low, uses less exemption per dollar of future exclusion captured.

The transfers are also irrevocable. The founder gives up ownership and, in a properly structured non-grantor trust, cannot take the assets back. A capable firm models this tradeoff explicitly, exclusion captured versus exemption consumed versus control surrendered, before any shares move.

This is where most stacking strategies fall apart. It is also where the difference between firms becomes most visible. The IRS applies the assignment-of-income doctrine to QSBS transfers.

The rule is direct: if a sale is already practically certain when shares are transferred, the IRS treats the gain as if the original holder realized it (see Hoensheid v. Commissioner, T.C. Memo. 2023-34, where a transfer two days before closing was disallowed). The transfer does not protect against taxes. The stacking structure collapses. In practical terms:

There is no IRS safe harbor based on a specific number of months. The test is facts and circumstances. As a practitioner heuristic, completing QSBS gifting or trust funding 12 to 24 months or more before any acquisition discussions begin puts transfers on the strongest footing. Funding trusts when equity value is still relatively low also reduces gift tax exposure at the time of transfer.

In May 2026, Treasury’s assistant secretary for tax policy publicly warned that guidance limiting QSBS stacking is forthcoming, telling practitioners, “Let me just warn you: We don’t like stacking.”

No guidance has been issued as of this writing, but the stated concern targets structures that go beyond one trust per distinct beneficiary, such as overlapping combination trusts created only to manufacture additional taxpayers.

This is where firm quality matters most. Carbon copy trusts, meaning multiple structurally identical trusts with the same terms, the same trustee, and the same beneficiaries, are the target fact pattern, and the IRS may point to the multiple-trust rule of Section 643(f), though its application to Section 1202 structures is not settled.

Defensible structures show genuine differentiation backed by real estate planning purpose: distinct beneficiaries or beneficiary classes, separate independent trustees, distinct dispositive terms, separate EINs and tax filings, and documented non-tax purposes for each trust.

A firm that proposes a stack of identical trusts is creating audit exposure, not tax savings.

Not every firm that mentions QSBS stacking can actually deliver it. These are the capabilities worth evaluating before committing to an advisor.

Peyton Carr, co-founder and managing partner of Keystone Global Partners, is recognized as one of the leading QSBS specialists in the country. His work is grounded in practical implementation, not textbook knowledge of the rules.

The firm works exclusively with venture-backed tech founders facing exits exceeding $20 million. Keystone engages founders through the Personal Exit Advisory® program, beginning 0 to 3 years before an anticipated liquidity event. This long runway is not a marketing choice. It is a requirement for executing strategies like QSBS stacking correctly.

If you are a founder with qualifying QSBS and a potential exit in the next one to three years, the planning decisions you make in this period will have more impact than anything you can do at the closing table.