QSBS Exclusion in 2026: What Founders and Early Employees Need to Know After OBBBA

If you hold stock in a qualifying startup, the rules for how much of your gain is tax-free just changed — but only if your stock was issued after July 4, 2025. The One Big Beautiful Bill Act (OBBBA) rewrote Section 1202 of the tax code, the provision behind Qualified Small Business Stock (QSBS). There are now two separate QSBS regimes running side by side, and which one applies to your shares depends entirely on when you got them — the difference between waiting five full years to sell tax-free and selling a portion, tax-free, in year three.

Key Takeaways

• QSBS acquired after July 4, 2025 gets a new tiered exclusion schedule. Instead of an all-or-nothing five-year cliff, you can now exclude 50% of gain at 3 years held, 75% at 4 years, and 100% at 5 years.
• QSBS acquired on or before July 4, 2025 keeps the old rules. Same 100% exclusion, but only after a full 5-year hold, and under the old, lower caps — no early partial benefit.
• The per-issuer gross asset limit rose from $50 million to $75 million. More companies qualify as “small” for QSBS purposes at the time stock is issued, which matters for later-stage startups that previously fell outside the window.
• The per-taxpayer gain exclusion cap rose from $10 million to $15 million (or 10 times your basis, if greater) for stock issued after July 4, 2025 — a real increase in how much gain can be shielded per issuer.
• The math isn’t free money. Gain excluded under the new 3-year or 4-year tiers still leaves a taxable slice, and that slice is taxed at a 28% rate plus the 3.8% net investment income tax — not the lower long-term capital gains rates.

What QSBS is and what just changed

Section 1202 of the Internal Revenue Code lets eligible shareholders exclude some or all of their gain from selling stock in a qualified small business — generally a domestic C corporation under a statutory gross-asset ceiling at issuance, engaged in an active trade or business other than a short list of excluded industries (most personal services, banking, farming, hotels, and a few others). Read the full statute at 26 U.S.C. § 1202.
Before OBBBA, the rule was unforgiving: hold your QSBS five years, and up to 100% of gain (capped at the greater of $10 million or 10x basis) was excluded. Hold it four years and 364 days, and you got nothing extra for the wait — no partial credit.
OBBBA, signed into law July 4, 2025, changed that structure for stock acquired after that date — one piece of a broader set of changes the bill made; see our overview of how the One Big Beautiful Bill affects entrepreneurs for the bigger picture:

• Held 3 years: 50% of gain excluded
• Held 4 years: 75% of gain excluded
• Held 5+ years: 100% excluded (same as the old regime’s top benefit)

Two other numbers moved at the same time: the per-issuer gross asset threshold rose from $50 million to $75 million (indexed for inflation starting tax years after 2026), and the per-taxpayer gain exclusion cap rose from $10 million to $15 million, or 10x basis if greater (also indexed after 2026).
The single most important question this article answers is which regime applies to your shares — the two systems produce very different outcomes, and the dividing line is a specific calendar date, not a tax year.

Old QSBS vs. new QSBS: which regime applies to you

QSBS is generally treated as “acquired” on the date the stock was issued to you — the exercise date for an option, the closing date for a direct purchase, or the conversion date for certain convertible instruments (SAFEs and notes get technical here — worth routing to an advisor).

If you exercised founder shares or options before July 4, 2025, you’re on the old track: full five-year wait, $50 million ceiling at issuance, $10 million cap. New grants or exercises today are on the new track — and the clock starts from your acquisition date, not OBBBA’s signing date.
One nuance worth flagging: a single founder can hold both kinds of QSBS simultaneously. Shares from an early-2024 exercise and a 2026 refresh grant are tracked separately, each on its own clock, under its own regime. Cap table hygiene — knowing exactly when each tranche was issued — matters more now than under the old cliff-only rule.

Why it matters: a worked example

Consider an illustrative case (not a real client): a startup engineer named Priya exercises incentive stock options on September 15, 2025 — after the cutoff, so her shares fall under the new tiered regime. Her exercise cost is $41,300, and the company’s gross assets are well under $75 million, so the stock qualifies as QSBS.
Suppose the company is acquired and Priya sells on October 2, 2028 — just over three years after acquisition — for $1,260,000, a gain of $1,218,700.

• She crossed the 3-year mark but not the 4-year mark, so 50% of that gain — $609,350 — is excluded from federal income tax.
• The remaining $609,350 is taxed at a flat 28% rate plus the 3.8% net investment income tax — roughly 31.8% combined, not the lower long-term capital gains rates.
• Rough federal tax on the taxable slice: $609,350 × 31.8% ≈ $193,773 (illustrative; state tax excluded).

Compare that with waiting until October 2030 — five years out — where the full gain (assuming similar size) would qualify for 100% exclusion, subject to the $15 million cap, taxed at 0% federally. This is illustrative math to show the mechanism, not a projection — actual outcomes depend on continued small-business qualification, basis, state tax, and whether the $15 million/10x-basis cap binds at larger gains.

How it works in practice

• The holding period clock starts at issuance, not vesting. For options, that’s the exercise date — exercising early (and filing the 83(b) election) can start the QSBS clock sooner.
• The $75 million gross asset test is measured at issuance, not at sale. A company that grows past $75 million later doesn’t disqualify your existing shares.
• Get QSBS eligibility confirmed in writing from company counsel or the CFO at issuance — evidence you’ll want years later when substantiating the exclusion.
• Track acquisition dates per tranche. Batches exercised at different times can fall under different regimes, each with its own clock.

The catch

Five years — or even three — is a long time to be illiquid. The tiered exclusion softens the cliff but doesn’t create liquidity; you still need a buyer or exit event.
Not every startup qualifies. The active trade or business requirement excludes whole industries, and companies can fail the gross asset test at various points.
28% on partial-exclusion gain beats nothing, but it’s higher than standard long-term capital gains rates. Selling at year three or four isn’t the same outcome as waiting to year five — the 15%/20% long-term rates don’t apply to the non-excluded slice.
Two regimes running in parallel is a recordkeeping burden. Misclassifying a tranche can mean claiming an exclusion you’re not entitled to, or missing one you are.
State conformity varies. This article covers federal treatment only — many states have their own QSBS rules, and some don’t conform to the federal exclusion at all.

Strategy: what to actually do

• Nail down your acquisition date for every tranche, noting whether it falls before or after July 4, 2025.
• Get written confirmation of QSBS eligibility, including the gross asset figure used to qualify.
• Model 3-year, 4-year, and 5-year sale scenarios before any liquidity event or tender offer — the tax outcome differs meaningfully. If you’re weighing an acquisition specifically, see our guide to tax planning around a startup acquisition.
• Revisit early-exercise and 83(b) timing with the new tiers in mind — starting the clock even a few months earlier can shift which tier you land in.
• Run the numbers on what a sale actually nets you — our guide to calculating the potential value of cashing out startup shares walks through the mechanics alongside QSBS treatment.

Where Harness fits in

Figuring out whether your shares qualify as QSBS — and which regime applies — depends on facts that are easy to get wrong: the exact issuance date, whether a SAFE converted before or after July 4, 2025, whether the company met the gross asset and active-business tests at the right moment, and how the $15 million cap interacts with your basis. This is exactly the kind of multi-variable, document-heavy question a specialist tax advisor is built to untangle. Harness connects founders, early employees, and investors with tax advisors experienced in equity compensation and QSBS planning — including modeling how much founders can save under the QSBS exclusion — so you’re not guessing at a six- or seven-figure tax outcome on your own.

Putting it all together

Before you assume any QSBS exclusion applies to a sale, confirm three things:

1. When was the stock actually acquired — before or after July 4, 2025 — since that date determines which set of rules governs your shares.
2. Does the issuing company meet the active business, entity type, and gross asset tests, both at issuance and when you’re substantiating the exclusion.
3. How long have you held the stock, and does that clear the 3-, 4-, or 5-year threshold for your exclusion percentage — or the full 5-year cliff under the old regime.

Once you know where you stand, a tax advisor can help model after-tax proceeds at different holding periods and confirm the paperwork holds up.

Frequently Asked Questions

Does the new tiered QSBS exclusion apply to stock I already hold? Only if it was acquired after July 4, 2025. Stock acquired on or before that date stays under the prior rules: a full five-year hold for any exclusion, capped at the older $50 million gross asset threshold and $10 million (or 10x basis) gain cap.
What does “acquired” mean — grant date or exercise date? For options, QSBS is generally treated as acquired when the underlying stock is issued, typically the exercise date, not the grant date. SAFEs and convertible notes raise more complex timing questions worth confirming with an advisor.
Is the 50%/75%/100% exclusion automatic once I hit the holding period? No. The stock must independently qualify as QSBS — domestic C corporation, gross asset test met at issuance, qualifying active trade or business — under IRC Section 1202 before the holding-period exclusion applies.
What happens to gain that isn’t excluded under the 3-year or 4-year tiers? It’s taxed at a flat 28% federal rate plus the 3.8% net investment income tax, higher than the standard 15%/20% long-term capital gains rates.
Can I still get 100% exclusion if I hold new QSBS for exactly five years? Yes. The five-year, 100% tier is preserved — the new law adds earlier partial-exclusion options at three and four years without reducing the five-year benefit.
Does this change apply at the state level too? Not necessarily. This article covers federal treatment only. Many states have their own QSBS rules, and some don’t conform to the federal exclusion at all.
Where can I read the actual statute? The full text of Section 1202 is at law.cornell.edu. The IRS also publishes guidance at irs.gov.

Disclaimer:
This article should not be considered tax or legal advice and is provided for informational purposes only. Please consult a tax professional for your specific tax situation.

Tax related products and services provided through Harness Tax LLC. Harness Tax LLC is affiliated with Harness Wealth Advisers LLC, collectively referred to as “Harness Wealth”. Harness Wealth Advisers LLC is a paid promoter, internet registered investment adviser. Registration does not imply a certain level of skill or training. This article should not be considered tax or legal advice and is provided for informational purposes only. Please consult a tax and/or legal professional for advice specific to your individual circumstances. This article is a product of Harness Tax LLC.
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