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QSBS After the 2025 Overhaul: The Founder's Guide to Section 1202 (2026)

OBBBA rewrote QSBS for stock issued after July 4, 2025: tiered holding periods, a $15M cap, a $75M asset ceiling. What qualifies and how much is tax-free.

By the Acorn 9 teamReviewed by a licensed CPA on the Acorn 9 team

Qualified Small Business Stock (QSBS) is the most powerful tax benefit in the startup ecosystem: under IRC Section 1202, a founder or early investor can exclude millions of dollars of gain from federal tax entirely. In 2025 it got materially better — and materially more complicated, because there are now two sets of rules depending on when your stock was issued.

This guide covers the current 2026 landscape: both vintages, what qualifies, and how the exclusion is actually computed.

The 2025 overhaul: two vintages

The One Big Beautiful Bill Act (OBBBA), signed July 4, 2025, created a second QSBS regime. The dividing line is the issuance date of your stock, tracked per block — a founder can hold both vintages in the same company and must account for each separately.

Issued on/before Jul 4, 2025Issued after Jul 4, 2025
Holding period → exclusion5+ yrs → 100% (no exclusion below 5)3 yrs → 50%, 4 yrs → 75%, 5+ yrs → 100%
Per-issuer dollar capgreater of $10M or 10× basisgreater of $15M or 10× basis (indexed from 2027)
Gross-assets ceiling$50M$75M (indexed from 2027)

Two consequences worth internalizing:

  • You cannot reset old stock into the new regime. Pre-enactment stock sold after July 4, 2025 still uses the $10M cap and the 5-year/100%-only rule. A stock-for-stock exchange or a §1045 rollover does not change the original acquisition date.
  • The new tiers give partial liquidity earlier. Under the old rules, selling at year 4 meant zero exclusion. Post-OBBBA stock held 4 years gets 75% excluded — a real change for founders facing an earlier exit.

How the exclusion is computed

Two numbers interact:

  1. Exclusion percentage — set by your vintage and holding period (the table above).
  2. Per-issuer cap — the greater of the dollar cap or 10× your adjusted basis.

Excluded gain = the lesser of (exclusion % × total gain) and the cap. Whatever remains is taxable.

Interactive

QSBS exclusion estimator

Federal §1202 only. Assumes the stock already qualifies (C-corp, qualified trade, gross-assets test met).

When was the stock issued?

Enter your gain, basis, and holding period to estimate how much §1202 can exclude.

Estimate only, federal §1202 exclusion. Does not check eligibility (qualified trade, C-corp status, gross-assets ceiling) and does not include state tax — California, Pennsylvania and others do not conform and tax the gain in full. Confirm with your CPA.

For a founder with near-zero basis, the dollar cap binds: 10× of ~$0 is ~$0, so the $15M (or $10M) figure controls. The 10x-basis lever only matters when basis is high — an investor with $3M of basis gets a $30M cap, and 10x becomes the better number.

Eligibility — where most people fall out

The exclusion is worthless if the stock was never QSBS to begin with. All of the following must hold:

  • Domestic C-corporation at issuance and during substantially all of the holding period. LLCs, partnerships, and S-corps do not issue QSBS — though converting to a C-corp can start the clock from the conversion.
  • Original issuance: you acquired the stock directly from the company (for cash, property, or services), not on the secondary market.
  • Gross-assets test: the company's aggregate gross assets were at or below the ceiling ($50M / $75M) at all times before, and immediately after, your stock was issued.
  • Active business: at least 80% (by value) of the company's assets are used in the active conduct of a qualified trade or business.

Excluded businesses (the most common disqualifier)

Section 1202(e)(3) excludes entire fields. If the company's principal activity is any of these, the stock does not qualify regardless of size or holding period:

  • Professional services: health, law, engineering, architecture, accounting, actuarial science, consulting, performing arts, athletics, financial services, brokerage
  • Banking, insurance, financing, leasing, investing or similar
  • Farming, mining/extraction, and hotels, restaurants, or similar hospitality businesses
  • Any business whose principal asset is the reputation or skill of one or more employees

A SaaS or hard-tech startup typically qualifies. A fintech doing "financial services," a telehealth company doing "health," or a solo consultant's C-corp typically do not. This gating is fact-intensive — get a determination.

The tax on the rest, and the AMT footnote

The taxable portion (gain above the cap, or the non-excluded share at the 50%/75% tiers) is taxed at the 28% Section 1202 rate plus 3.8% NIIT — about 31.8% federally, not the 15%/20% long-term rate. The excluded portion is fully federal-tax-free and outside NIIT.

The old "7% AMT preference" on excluded QSBS gain only ever applied to stock issued before September 28, 2010. For any modern founder it is obsolete — OBBBA also removed any AMT preference for the new tiers.

State conformity will surprise you

QSBS is a federal exclusion. States decide separately:

  • California does not conform — it taxes the full gain at up to 13.3%, even when 100% is excluded federally. For a California founder, "tax-free QSBS" can still mean a seven-figure state bill.
  • Pennsylvania, Alabama, Mississippi also do not conform.
  • New Jersey begins conforming in 2026.

Run your state separately. The calculator above is federal only.

Planning levers (advisor territory)

  • §1045 rollover — held 6+ months but will miss the threshold? Reinvest proceeds into new QSBS within 60 days to defer; the holding period tacks. (Cannot convert vintages.)
  • Stacking — because the cap is per-taxpayer-per-issuer, gifting QSBS to additional taxpayers (especially non-grantor trusts, which are separate taxpayers) can multiply the exclusion. Grantor trusts do not create an extra cap. Note: Treasury signaled in May 2026 it is reviewing aggressive stacking, and anti-abuse doctrines (§643(f), assignment of income) constrain last-minute structures. Strictly advisor-only.

Bottom line

If your stock was issued after July 4, 2025, you have a more generous and more flexible QSBS than any founder before you — up to $15M excluded per company, with partial exclusions starting at year 3. If it was issued earlier, the old $10M/5-year rule still governs that block. Either way, the exclusion is only real if the stock qualified at issuance, and your state may tax the gain regardless. Model the federal number above, then confirm eligibility and state treatment with your CPA.


This guide is informational only and is not tax advice. Sources: 26 USC §1202 · OBBBA, Pub. L. 119-21 §70431 (enacted July 4, 2025) · AICPA, The Tax Adviser (Nov 2025) · Perkins Coie, Grant Thornton, and Mintz OBBBA analyses. Reviewed by a licensed CPA on the Acorn 9 team.

FAQ

Frequently asked questions

What changed about QSBS in 2025?
The One Big Beautiful Bill Act (signed July 4, 2025) created a second QSBS regime for stock issued AFTER that date. New-vintage stock gets tiered exclusions — 50% at 3 years, 75% at 4 years, 100% at 5 years — a per-issuer cap of the greater of $15M or 10x basis (up from $10M), and a $75M gross-assets ceiling (up from $50M). Stock issued on or before July 4, 2025 keeps the old rules: 100% only at 5 years, $10M / 10x cap, $50M ceiling. You cannot convert old-vintage stock into the new regime.
How much gain can I exclude with QSBS?
Per issuer, the greater of the dollar cap ($15M for post-July-2025 stock, $10M for earlier stock) or 10 times your adjusted basis, multiplied by the holding-period exclusion percentage. For a founder with near-zero basis, the dollar cap controls: a 2026-issued founder holding 5+ years can exclude up to $15M of gain per company. The 10x-basis lever only beats the dollar cap when your basis is high (e.g. a $3M basis gives a $30M cap).
Does my startup qualify for QSBS?
The company must be a domestic C-corporation at issuance and through substantially all of your holding period, with aggregate gross assets at or below the ceiling ($50M old / $75M new) at and immediately after issuance, and at least 80% of assets used in a qualified trade or business. Critically, several fields are excluded outright: health, law, engineering, architecture, accounting, actuarial science, performing arts, consulting, athletics, financial services, brokerage, banking, insurance, financing, leasing, farming, mining, and hospitality (hotels/restaurants). A startup whose principal asset is the reputation or skill of its employees also fails.
What tax rate applies to the gain that is NOT excluded?
The taxable portion of QSBS gain is taxed at the special 28% Section 1202/collectibles capital-gains rate, plus the 3.8% net investment income tax — roughly 31.8% federal. The excluded portion is fully tax-free at the federal level and is not subject to NIIT. For stock acquired after September 27, 2010 (and all post-OBBBA stock), there is no AMT add-back.
Does my state honor QSBS?
Not always. California does not conform to Section 1202 at all — it taxes the full gain at rates up to 13.3% even when 100% is excluded federally. Pennsylvania, Alabama, and Mississippi also do not conform. New Jersey begins conforming in 2026. A federal QSBS estimate is not your total-tax picture; check your state.
What if I'll miss the holding period?
Section 1045 lets you defer the gain by rolling the proceeds into new QSBS within 60 days of sale, if you held the original stock at least 6 months; the holding period tacks on. Note a §1045 rollover cannot convert pre-July-2025 stock into the new post-OBBBA regime — the original acquisition date still controls.