QSBS Section 1202 Exclusion: How to Exclude Up to $10M+ of Capital Gains on a Business Sale (2026)

QSBS is the single largest legal tax break available to founders selling a business in the United States. Under Section 1202 of the Internal Revenue Code (codified in 1993, expanded by the PATH Act in 2015), eligible founders can exclude up to $10 million of federal capital gains on the sale of qualified C-corporation stock held for at least five years. For founders with substantial unrealized gain, the savings often exceed $2.5 million in federal tax. The catch: many founder-led businesses are structured as S-corps, LLCs, or partnerships, none of which qualify for QSBS without restructuring well before a sale event.

This guide explains who qualifies, how the exclusion is calculated, the operational requirements during the 5-year holding period, and the planning moves that founders should be making 2-5 years before a likely exit. It also covers the QSBS stacking strategies that sophisticated sellers use to multiply the $10M cap across family members, trusts, and grantor structures, which is how some founders walk away from $50M+ sales with most or all of the gain excluded.

We are CT Strategic Partners, a U.S. buy-side M&A firm based in Sheridan, Wyoming. We work with 76+ active capital partners across the lower middle market and we routinely walk founder-sellers through QSBS planning when their business is approaching the right stage. Our model is buyer-paid, sellers pay nothing, sign nothing, and walk away at any time. This page is educational. For tax planning specifically, you’ll need to engage a tax attorney or CPA; we can refer you to advisors in our network who specialize in QSBS structuring.

A note on the bar: QSBS planning is highly fact-specific and the IRS has tightened enforcement on aggressive stacking arrangements in recent years. This page provides the general framework but is not tax advice. The cost of mistakes is substantial, a botched QSBS election can disqualify the entire exclusion. Always work with qualified tax counsel.

The five qualification requirements for QSBS treatment

To qualify for QSBS exclusion, all five requirements must be satisfied on a particular share of stock:

1. Domestic C-corporation

The issuing entity must be a U.S. domestic C-corporation at the time the stock is issued, AND substantially the entire holding period. S-corporations, LLCs, partnerships, and foreign corporations do not qualify. A common mistake: founders convert their S-corp or LLC to C-corp shortly before a sale, but the conversion does NOT establish a new QSBS holding period, the pre-conversion period doesn’t count.

2. Gross asset test ($50M cap)

At the time the stock is issued (and at all times immediately after), the corporation must have aggregate gross assets of $50 million or less. Gross assets is measured at fair market value of the assets contributed plus cash, not at book value. The $50M test only applies at issuance, the company can grow beyond $50M afterward and the original QSBS still qualifies.

3. Active qualified trade or business

During substantially all of the 5-year holding period, at least 80% of the corporation’s assets must be used in the active conduct of a qualified trade or business. Disqualified businesses: any professional service business (law, accounting, consulting, engineering, architecture, medical, financial services, brokerage), banking/finance/leasing, farming, mining, hospitality, restaurants. Most home services, manufacturing, B2B services, SaaS, and consumer brands DO qualify.

4. Original issuance requirement

The founder must acquire the stock directly from the corporation at original issuance, not from another shareholder via secondary purchase. Stock acquired via gift or inheritance from an original QSBS holder can also qualify (the original holding period tacks on).

5. Five-year holding period

The stock must be held for more than five years before sale. The holding period starts on the date of original issuance. For founders, this is usually the date of incorporation or the date of original stock subscription. Critical planning point: if a founder is considering selling in year 3 or 4 of a business, accelerating the sale to capture early-stage value often costs $1-3M more in federal taxes than waiting to year 5.

Calculating your QSBS exclusion: the $10M vs 10x basis test

The QSBS exclusion is the greater of two limits:

• $10 million in eligible gain (per shareholder, per company), OR
• 10 times the shareholder’s adjusted basis in the stock

For founders who contributed nominal cash ($1,000 to incorporate, for example), 10x basis is trivial and the $10M cap controls. For founders who later contributed significant capital, the 10x basis test can exceed $10M and unlock additional exclusion.

Worked example: $20M sale, founder $1,000 basis

Founder incorporated company in 2018 with $1,000 of paid-in capital. Sells 100% of QSBS stock in 2026 for $20M.

• Total gain: $19,999,000
• QSBS exclusion limit: max($10M, 10 × $1,000) = $10M
• Federal capital gains tax on excluded $10M: $0 (excluded from federal income tax entirely, no NIIT)
• Federal capital gains tax on remaining $9,999,000: approximately $2.38M (23.8% rate)
• Net federal savings vs no QSBS: approximately $2.38M

Stacking the exclusion across family members

Each individual shareholder gets their own $10M cap. Founders who pre-plan can transfer QSBS stock to a non-grantor trust for each child or grandchild, with each trust getting its own $10M exclusion. A founder with three children + two grandchildren could potentially stack five $10M exclusions = $50M of total exclusion. State-tax considerations vary; many founders set up trusts in tax-friendly states (South Dakota, Nevada, Wyoming) to avoid state-level capital gains.

Section 1202(h), partial exclusions for pre-2010 stock

QSBS issued before September 27, 2010 gets a reduced exclusion (50% for pre-2/18/2009 stock, 75% for stock issued 2/18/2009 to 9/27/2010, 100% for post-9/27/2010 stock). 7% AMT preference applies to the partial-exclusion stock but NOT to fully-excluded stock.

Common mistakes that disqualify QSBS treatment

The IRS has been actively challenging QSBS positions on examinations. The most common disqualifications:

1. Stock not originally issued

Founder bought out a co-founder’s shares mid-stream. The acquired shares are NOT QSBS, they were not acquired at original issuance. Only original-issuance stock qualifies.

2. Disqualified service business categorization

The IRS has been aggressive in arguing that what founders consider a ‘product business’ is actually a disqualified service business. Real cases where QSBS was denied: investment-management firms claiming to be SaaS, consulting firms claiming to be technology businesses, marketing agencies claiming to be product companies. The 80% asset test must be passed with verifiable documentation.

3. S-corp election preserved past stock issuance

If the corporation was an S-corp at any point during the holding period AFTER the stock was ‘issued as QSBS’, the QSBS treatment is forfeited. The C-corp election must be maintained continuously.

4. Stock acquired via 1031-like exchange or 351 contribution

Stock received in exchange for property under §351 contribution generally does NOT qualify as QSBS unless the contributed property was itself QSBS. This catches many entrepreneurs who roll an old business into a new C-corp expecting QSBS treatment.

5. Insufficient documentation

Founders must be able to prove (a) C-corp status at issuance, (b) $50M gross-asset compliance at issuance, (c) active-trade-or-business compliance during the 5-year period, and (d) original-issuance proof. Bad recordkeeping is the most common audit-failure mode.

Planning moves to make 2-5 years before a sale

If you’re currently an LLC or S-corp

Convert to C-corp immediately if a sale is 5+ years away. The QSBS clock starts at conversion, not at original founding. A $20M sale in 2031 with a 2026 conversion captures the full $10M exclusion. A 2029 conversion ahead of a 2030 sale captures nothing.

If a sale is <5 years away, evaluate whether the projected tax savings justify the conversion costs (double-taxation in interim years for C-corp). For mid-market businesses with $2M+ EBITDA, the math usually favors conversion.

Trust planning for stacking

Establish non-grantor trusts for family members in tax-friendly states. Transfer QSBS stock to each trust. Each trust becomes a separate QSBS holder with its own $10M exclusion. The gift triggers gift-tax accounting but the QSBS is then sale-protected.

Document everything from day 1

Maintain detailed records of: incorporation date, asset values at issuance, gross-asset compliance throughout the 5-year period, active-trade-or-business operations, and original-issuance proof for each share. Many founders lose QSBS treatment not because of substance but because of audit-time documentation gaps.

Engage tax counsel early

QSBS is one of the most fact-specific areas of tax law. The cost of a $25-50k QSBS planning engagement is trivial compared to the $2-5M federal tax savings on a successful exclusion. Don’t wait until the LOI is signed.

How QSBS interacts with the sale process

Asset sale vs stock sale

QSBS only excludes gain on the sale of stock, not asset sales. If the buyer insists on an asset purchase (very common for tax reasons), the QSBS exclusion is lost. This is a major negotiation point, sellers with QSBS-eligible stock should push hard for stock sale structure, often accepting a 5-10% lower headline price in exchange for the tax savings.

Section 338(h)(10) election

A 338(h)(10) election allows the IRS to treat the stock sale as an asset sale for buyer tax purposes (giving the buyer step-up in basis) while preserving stock-sale treatment for the seller in some cases. QSBS treatment is generally retained.

Rollover equity and QSBS

If the seller rolls over equity into the buyer’s entity (typical in PE deals), the rollover portion does NOT qualify for QSBS exclusion. The exclusion applies only to the cash-out portion. Many founders structure to take maximum cash up to the $10M exclusion limit, then roll equity for the remainder.

Frequently Asked Questions

What is the maximum QSBS exclusion?

The greater of $10 million per shareholder per company, OR 10 times the shareholder’s adjusted basis in the stock. For most founders with nominal basis ($1,000-$10,000), the $10M cap controls. Sophisticated sellers stack the exclusion across non-grantor trusts for family members, multiplying the total exclusion.

Does my LLC qualify for QSBS?

No. QSBS requires C-corporation stock. LLCs, S-corporations, and partnerships do not qualify. However, converting your LLC to a C-corp starts a fresh 5-year QSBS holding period. If you’re planning to sell in 5+ years, the conversion almost always pays for itself in tax savings.

Which industries are disqualified from QSBS?

Professional services (law, accounting, consulting, engineering, architecture, medical, financial services, brokerage), banking, insurance, financing, investment management, leasing, farming, mining, hospitality, and restaurants are all disqualified. Most home services, manufacturing, B2B services, SaaS, and consumer-brand businesses DO qualify.

How much federal tax does QSBS save me?

On a $10M excluded gain, you save approximately $2.38M in federal capital gains tax (23.8% rate combining 20% LTCG + 3.8% NIIT). State savings vary; states like California still tax the gain at the state level, but states like Wyoming, South Dakota, Nevada, and Texas don’t tax capital gains at all.

Can I stack QSBS across family members?

Yes. Each individual shareholder (including non-grantor trusts established for family members) gets their own $10M cap. With proper trust planning across multiple beneficiaries, founders can stack 3-5+ exclusions, potentially excluding $30-50M+ of total gain. The setup must happen well before the sale event.

What if I sell before 5 years?

You lose QSBS treatment entirely on that sale. However, Section 1045 allows you to roll the proceeds into NEW QSBS-eligible stock within 60 days, preserving the holding period. This is useful for founders forced to sell early but planning a serial-entrepreneur path.

How do I document QSBS compliance?

Maintain detailed records of (1) original incorporation date and original stock issuance documents, (2) gross-asset valuations at issuance, (3) ongoing documentation that 80%+ of assets are used in the active qualified trade or business, (4) shareholder roster with acquisition dates, and (5) annual confirmation of C-corp status. The IRS has been increasing QSBS audit activity since 2020.

What’s the difference between QSBS Section 1202 and Section 1045?

Section 1202 is the exclusion, held 5+ years, exclude gain. Section 1045 is the rollover, if you sell before 5 years, you can defer the gain by reinvesting in new QSBS within 60 days, and the holding period tacks. Both are powerful but Section 1202 is the primary play for most exits.

Will QSBS treatment survive future tax law changes?

QSBS has been bipartisan-supported since 1993 and was expanded in 2015. Multiple proposed tax-reform bills (under both administrations) have left QSBS largely intact. However, the $50M gross-asset cap and other parameters could change. The conservative move is to convert and start the 5-year clock under current rules.

Authoritative tax sources cited in this report:

• IRS.gov, Internal Revenue Service guidance and publications
• IRS Internal Revenue Bulletin, Revenue rulings, procedures, and notices
• 26 U.S. Code (Internal Revenue Code), Statutory text
• Tax Foundation, State and federal tax policy research

This article is informational and not tax or legal advice. Consult a qualified CPA or tax attorney for your specific situation.

Sources & References

• IRC Section 1202, Cornell Law
• IRC Section 1045, rollover provisions
• PATH Act of 2015, extended 100% exclusion permanently
• Treasury Regulations on QSBS, TD 9778, related rulings
• Industry resources: NAEPC, AICPA Tax Section QSBS guidance, ABA Tax Section Section 1202 working group

Last updated: May 16, 2026. For corrections or methodology questions, get in touch.

Reference: the 2026 Founder Rollover Equity Benchmark Report is the deeper research piece on this topic.