QSBS Exclusion Guide

What Qualified Small Business Stock Is

Qualified small business stock is a special category of stock that Congress created in 1993 to channel investment into small, growing companies. The reward is one of the largest breaks in the tax code: IRC §1202 lets an individual exclude part or all of the capital gain on the sale of QSBS from federal income tax. For stock that qualifies for the full exclusion, a multi-million dollar gain can come out entirely tax-free at the federal level.

The exclusion is available only to non-corporate taxpayers: individuals, and through them trusts and pass-through entities, but not C corporations. The stock itself must be issued by a domestic C corporation, you must acquire it at original issue, and you must hold it for a required period that depends on when you bought it. The combination of a C corporation issuer and a non-corporate holder is the core of the rule, and it is why founders and early investors who organize as a C corporation can later claim the break, while those who use an LLC or S corporation generally cannot.

Three numbers control how much you exclude: the exclusion percentage (set by your acquisition date and holding period), the per-issuer cap (the greater of a dollar limit or ten times your basis), and the company's gross assets at issuance (which must stay under a ceiling for the stock to qualify at all). The rest of this guide works through each, starting with the 2025 overhaul that changed all three.

The 2025 OBBBA Overhaul of Section 1202

For more than a decade, §1202 had a single shape: hold QSBS for more than five years and exclude 100% of the gain, up to the greater of $10 million or ten times basis, from a company whose gross assets never topped $50 million. The One Big Beautiful Bill Act (P.L. 119-21), enacted July 4, 2025, rewrote that for stock acquired after the enactment date while leaving older stock alone.

Three things changed for stock acquired after July 4, 2025:

• A tiered exclusion replaced the all-or-nothing five-year rule. You now exclude 50% after a three-year hold, 75% after four years, and 100% after five years. Before, selling at year four gave you nothing.
• The per-issuer dollar cap rose from $10 million to $15 million. The ten-times-basis alternative is unchanged, and the $15 million figure is indexed for inflation for tax years after 2026.
• The company gross-asset ceiling rose from $50 million to $75 million. More and larger companies can now issue QSBS, and this ceiling is also indexed after 2026.

The dividing line is the acquisition date, not the sale date. Stock you already held on July 4, 2025 keeps the old rules forever, even if you sell it years later. Stock issued to you the next day uses the new tiered rules. That makes the acquisition date the single most important fact in any QSBS analysis, and the first thing this guide's calculator asks for.

How Much You Exclude: The Two Regimes

The exclusion percentage is locked by the date you acquired the stock, then unlocked by your holding period. The table maps both:

For older stock, the percentage is frozen at the rule in effect when you bought it. A longer hold gets you across the five-year line, but it never upgrades the percentage. Someone who bought in 2008 and held twelve years still excludes only 75%, because that was the rule on the acquisition date. The holding period qualifies you; the acquisition date sets the rate.

For OBBBA stock the percentage rises with the hold under the new tiered table (§1202(a)(5)): 50% at three years, 75% at four, and the full 100% at five. This is genuinely new flexibility, and it changes the calculus around an early exit, which the practitioner notes below explore.

The Per-Issuer Cap: Greater of the Dollar Limit or 10x Basis

The exclusion is not unlimited. For each issuing company, the gain eligible for exclusion is capped at the greater of two amounts under §1202(b):

• The dollar cap: $15 million for stock acquired after July 4, 2025, or $10 million for older stock, reduced by any eligible gain from the same company you excluded in prior years. Married filing separately uses half.
• Ten times your basis: ten times your aggregate adjusted basis in the company's QSBS that you sold during the year, computed without later additions to basis.

For most investors who paid cash for stock, the dollar cap is the binding limit, because ten times a modest cash basis is small. The ten-times-basis test matters for founders and others who received stock in exchange for substantial property or intellectual property, where a high basis can lift the cap well above the dollar figure. The calculator computes both and uses whichever is larger.

Gain above the per-issuer cap is not lost, but it is not excluded either: it is a normal long-term capital gain taxed at 0%, 15%, or 20%, plus the 3.8% Net Investment Income Tax if it applies. The cap is per company, so an investor who holds QSBS in two different qualifying companies gets a separate cap for each.

The Qualification Tests: What Makes Stock QSBS

The exclusion only applies if the stock actually meets the QSBS definition. The main tests under §1202(c) and (d) are:

• Domestic C corporation. The issuer must be a U.S. C corporation at original issue and for substantially all of your holding period. S corporations, LLCs, and partnerships do not issue QSBS.
• Gross-asset ceiling at issuance. The company's aggregate gross assets must not have exceeded the ceiling ($50 million for older stock, $75 million for OBBBA stock) at any time before, and immediately after, the stock was issued. A company can grow past the ceiling later; what matters is its size when your stock was issued.
• Original issue. You must acquire the stock directly from the company (or through an underwriter) at its original issue, in exchange for money, other property (not stock), or services. Buying shares on the secondary market from another shareholder does not produce QSBS in your hands.
• Active business requirement. During substantially all of your holding period, at least 80% of the company's assets (by value) must be used in the active conduct of a qualified trade or business.
• No major redemptions. Certain stock buybacks by the company around the time of your purchase can disqualify the stock under the redemption rules.

These tests are factual and unforgiving. A company that crossed the gross-asset ceiling before issuing your stock, or that parked too much cash in passive investments, can fail even if everything else looks right. Serious QSBS planning starts with the company confirming and documenting its status at each financing round, not at the sale.

Which Businesses Cannot Issue QSBS

The active-business requirement carves out whole industries. A qualified trade or business under §1202(e)(3) is essentially any business except:

• Personal-service fields where the principal asset is the reputation or skill of employees: health, law, engineering, architecture, accounting, actuarial science, performing arts, consulting, athletics, financial services, and brokerage services.
• Banking, insurance, financing, leasing, investing, and similar businesses.
• Farming (including raising or harvesting trees).
• Mining and extraction of natural resources eligible for percentage depletion.
• Operating a hotel, motel, restaurant, or similar business.

This is why QSBS is so closely associated with technology, manufacturing, retail, and product companies, and why a consulting firm, a medical practice, or a hedge fund generally cannot offer it, even if organized as a small C corporation. The line can be subtle: a software company that sells a product usually qualifies, while one that mainly sells the personal expertise of its consultants may not. When a business sits near the boundary, the qualification opinion is the most important document in the file.

The 28% Rate and AMT Preference on Partial Exclusions

A 100% exclusion is clean: no taxable gain, no AMT issue. The 50% and 75% exclusions are where the hidden costs live, and they surprise people who assume the leftover gain is just a normal capital gain.

First, the rate. The part of the eligible gain that is not excluded is §1202 gain, and IRC §1(h) taxes it at a maximum 28% rate, not the 15% or 20% long-term capital gains rate. On top of that, the taxable portion can carry the 3.8% Net Investment Income Tax, so the combined federal rate on the non-excluded slice can reach 31.8%. A 50% exclusion does not halve your tax; it excludes half the gain and then taxes the other half at a higher rate than ordinary capital gains.

Second, the AMT. Under IRC §57(a)(7), 7% of the excluded gain is an alternative minimum tax preference item for 50% and 75% exclusion stock. So even the excluded portion is not entirely outside the tax system: a sliver of it can be pulled back through the AMT. The 100% exclusion (post-September 27, 2010 stock held five years, and OBBBA stock held five years) has no AMT preference, which is a large part of why the 100% exclusion is the gold standard.

The Section 1045 Rollover: Buying Time

What happens when a sale is forced before you reach the exclusion threshold, for example when your company is acquired at year two? IRC §1045 is the answer. It lets you defer the gain from QSBS held more than 6 months by reinvesting the sale proceeds in new QSBS within 60 days of the sale.

The mechanics: the deferred gain reduces the basis of the replacement QSBS, and your original holding period tacks onto the new stock. You have not excluded the gain; you have rolled it into a fresh investment and kept the clock running. When you eventually sell the replacement stock and clear the holding-period threshold, the exclusion applies to that sale. In effect, §1045 turns a premature exit into a deferral that preserves the path to a later exclusion.

The rollover is most valuable in the new OBBBA world for a different reason. Because OBBBA stock already earns 50% at three years and 75% at four, the rollover is now the tool for getting a sub-three-year exit back onto a qualifying track, rather than the all-or-nothing rescue it used to be under the five-year-only rule. The election is made on the return, and the 60-day window is strict, so the decision to roll has to be made quickly after a sale.

Cap Stacking and State Conformity

Two advanced points separate a good QSBS outcome from a great one.

Cap stacking. The per-issuer dollar cap is per taxpayer, and a non-grantor trust is a separate taxpayer with its own cap. By gifting QSBS to one or more properly structured non-grantor trusts well before a sale, a founder can multiply the number of $10 million or $15 million caps available against a single company's gain. Done correctly and early, with genuine irrevocable transfers, stacking can turn a single $15 million exclusion into several. Done late or carelessly, it fails and can trigger gift-tax problems, so it is squarely advisor territory.

State conformity. The exclusion is a federal rule, and not every state follows it. California does not allow the §1202 exclusion at all, taxing the full gain. New Jersey and Pennsylvania (for individuals) have historically not conformed. Many states that start from federal taxable income do follow it, but the only safe approach is to confirm your specific state before treating the gain as fully tax-free. On a large gain, the state tax on a non-conforming state can be the single biggest cost that remains after a perfect federal exclusion.

For the income-tax side of any taxable leftover, the Net Investment Income Tax guide and the Qualified Dividends & Capital Gains Tax Calculator cover how the 3.8% surtax and the capital-gains brackets stack on top.

Practitioner Insight

Real-World Scenarios

When the QSBS Rules Do Not Apply

• You are a C corporation. The exclusion is only for non-corporate taxpayers. A C corporation that holds the stock gets no §1202 exclusion.
• The issuer was an S corp, LLC, or partnership. Only stock in a C corporation can be QSBS. Converting to a C corporation starts a fresh clock and a fresh gross-asset test from the conversion.
• You bought on the secondary market. Stock purchased from another shareholder, rather than at original issue from the company, is not QSBS in your hands.
• The company was too big at issuance. If gross assets topped the ceiling before or right after your stock was issued, the stock never qualified, regardless of how the company looks now.
• The business is on the excluded list. Health, law, consulting, finance, farming, hospitality, and similar businesses generally cannot issue QSBS.
• You did not meet the holding period and cannot roll. Without a §1045 rollover, a sale before the threshold gets no exclusion.
• Your state does not conform. A perfect federal exclusion can still leave a full state tax bill in California and other non-conforming states.

Frequently Asked Questions

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