Section 1202 QSBS Exclusion: Tax-Free Startup Gains

Key Takeaways

• Section 1202 QSBS exclusion can shield up to 15 million dollars of gain, or 10 times your basis, per company.
• Stock acquired after July 4, 2025 follows a tiered schedule: 50, 75, and 100 percent at 3, 4, and 5 years.
• A frequent error is buying QSBS on the secondary market, which fails the original-issuance rule.
• The break only applies to C corporation stock, so entity choice at formation decides everything.

What the Section 1202 QSBS Exclusion Is

Section 1202 of the Internal Revenue Code lets a non-corporate taxpayer exclude part or all of the gain from selling qualified small business stock, often shortened to QSBS. The Section 1202 QSBS exclusion is the formal name for that benefit. The stock must be issued by a domestic C corporation that meets a size test, and you must hold it long enough to clear the required holding period.

The exclusion is capped per issuer. For each company, you can exclude the greater of a fixed dollar amount or 10 times your adjusted basis in the stock. That second prong matters most when you invest real cash rather than founding the company for almost nothing.

The Intuition

Congress wanted to steer private capital toward small, growing companies. A capital gains tax that takes 20 percent or more off the top reduces the reward for that risk. Section 1202 removes the tax on a defined slice of the upside, so the after-tax payoff for backing a startup early can be far larger than for a public stock.

The design rewards patience and original ownership. You have to buy the stock at issuance, hold it for years, and the company has to stay genuinely small when you invest. Those conditions point the benefit at true early-stage risk capital rather than late-stage trading.

How It Works

Three tests gate the exclusion. The stock must be originally issued to you by the corporation in exchange for money, property, or services. The company must be a domestic C corporation whose aggregate gross assets never exceeded the cap right after issuance. And the company must use at least 80 percent of its assets in a qualified active trade or business.

For stock acquired on or before July 4, 2025, you exclude 100 percent of eligible gain after holding more than 5 years, the per-issuer cap is 10 million dollars or 10 times basis, and the gross asset cap is 50 million dollars. For stock acquired after July 4, 2025, the One Big Beautiful Bill Act introduced a tiered schedule:

Holding period   Exclusion
3 years          50 percent
4 years          75 percent
5+ years         100 percent

The new law also raised the per-issuer cap to 15 million dollars, indexed for inflation, and lifted the gross asset ceiling to 75 million dollars. Any gain that is not excluded for stock held 3 or 4 years is taxed at a 28 percent rate, not the usual long-term rates.

Worked Example

Suppose you invest 200,000 dollars in a qualifying C corporation startup in 2026 and sell after holding more than 5 years for 8 million dollars. Your gain is 7.8 million dollars.

Per-issuer cap = greater of 15,000,000 or 10 x 200,000
               = greater of 15,000,000 or 2,000,000
               = 15,000,000
Eligible gain  = 7,800,000  (below the cap)
Excluded gain  = 7,800,000 x 100 percent = 7,800,000
Taxable gain   = 0

The full 7.8 million dollar gain escapes federal tax because it sits under the 15 million dollar cap and you cleared the 5-year hold. Had you sold at year 4 under the new rules, only 75 percent would be excluded.

Common Mistakes

1. Buying QSBS on the secondary market. The stock must be originally issued to you. Purchasing shares from another holder breaks the rule and disqualifies the gain.

2. Holding the stock through an S corporation or LLC. Only C corporation stock qualifies. Founders who pick a pass-through entity at formation lose access entirely.

3. Tripping the gross asset test. If the company's aggregate gross assets exceeded the cap at issuance, the stock never qualifies, even if it shrinks later.

4. Selling too early under the new tiered rules. For post-2025 stock, exiting at year 3 or 4 leaves part of the gain taxable at 28 percent. The full benefit needs 5 years.

5. Ignoring state conformity. Several states do not follow Section 1202. A gain that is federally tax-free can still face state income tax.

Frequently Asked Questions

What is the Section 1202 QSBS exclusion in simple terms? The Section 1202 QSBS exclusion lets you skip federal tax on much or all of the profit from selling stock in a small C corporation you backed early. You have to buy the stock at issuance and hold it for several years.

How does the Section 1202 QSBS exclusion affect investment decisions? It raises the after-tax return on early-stage C corporation investments, so founders often incorporate as C corporations specifically to preserve it. Investors track the holding-period clock closely, since selling before year 5 can forfeit part of the exclusion.

What is a real-world example of Section 1202? An investor who puts 200,000 dollars into a qualifying startup and sells for 8 million dollars after 5 years can exclude the entire 7.8 million dollar gain because it falls under the 15 million dollar per-issuer cap.

How can investors use Section 1202 effectively? Confirm C corporation status, verify the gross asset test at issuance, document the original-issuance date, and hold for the full 5 years. Some holders also split shares among family members to multiply the per-issuer cap.

How is Section 1202 different from Section 1244 stock? Section 1202 excludes gains on winning small business stock, while Section 1244 converts losses on failed small business stock into ordinary losses. One rewards success, the other softens failure.

Sources

1. Cornell Legal Information Institute. "26 U.S.C. 1202 - Partial exclusion for gain from certain small business stock." https://www.law.cornell.edu/uscode/text/26/1202
2. The Tax Adviser. "QSBS gets a makeover: What tax pros need to know about Sec. 1202's new look." https://www.thetaxadviser.com/issues/2025/nov/qsbs-gets-a-makeover-what-tax-pros-need-to-know-about-sec-1202s-new-look/
3. Baker Tilly. "Changes to Section 1202, Qualified Small Business Stock." https://www.bakertilly.com/insights/changes-to-section-1202-qualified-small-business
4. Grant Thornton. "Explaining enhanced Section 1202 benefits." https://www.grantthornton.com/insights/alerts/tax/2025/insights/explaining-enhanced-section-1202-benefits

Disclaimer

This article is educational content only and is not financial advice. Nothing here is a recommendation to buy, sell, or hold any security. Consult a licensed advisor before making investment decisions.