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QSBS §1202 vs. S-Corp/LLC Sale

Should you convert to a C-Corp for the Section 1202 exclusion, or sell as a pass-through entity? This tool compares the total tax burden of each path — including the C-Corp tax drag during operations — and calculates how many years before the conversion stops making sense.

Section 1202 QSBS requirements: C-Corporation • Stock held ≥5 years • Gross assets <$50M at issuance • Active qualified trade or business • Exclusion capped at the greater of $15M or 10× adjusted basis. See IRS Publication 550 for full eligibility criteria.

Business & Sale Details

$
$

Your original investment or capitalized cost in the business.

$

Annual taxable income at the entity level. As an S-Corp this has no entity tax; as a C-Corp it is taxed at the corporate rate.

years (minimum 5 for QSBS)

Tax Rates

%

20% federal long-term capital gains + 3.8% NIIT = 23.8%

% (PA default)
%

QSBS §1202 Parameters

$

The greater of $15M or 10× your adjusted basis. This tool calculates the effective cap automatically.

%

100% for stock acquired after 9/27/2010. Earlier vintages may be 50% or 75%.

Scenario A: Sell as S-Corp / LLC

Sale Price $5,000,000
Cost Basis $500,000
Capital Gain $4,500,000

Entity-Level Tax During Operations

Corporate tax paid (S-Corp = pass-through) $0

Exit Tax

Federal CG + NIIT (23.8%) ($1,071,000)
State Tax (3.07%) ($138,150)
Total Tax Burden ($1,209,150)
Net After-Tax Proceeds $3,790,850

Scenario B: Convert to C-Corp & QSBS Exit

Sale Price $5,000,000
Cost Basis $500,000
Capital Gain $4,500,000

C-Corp Tax Drag (5 Years)

Annual Corporate Tax (21% × $750,000) ($157,500)
Cumulative C-Corp Tax Drag ($787,500)

§1202 QSBS Exclusion at Exit

Effective Exclusion Cap $15,000,000
Gain Excluded (100%) $4,500,000
Remaining Taxable Gain $0
Federal + State Tax on Remaining Gain $0
Total Tax Burden (Drag + Exit) ($787,500)
Net After-Tax Proceeds $4,212,500

The Bottom Line

The QSBS path saves $421,650 after accounting for the C-Corp tax drag.

Even after paying $787,500 in cumulative corporate tax over 5 years, the Section 1202 exclusion saves $1,209,150 at exit — a net benefit of $421,650.

Breakeven Analysis

Breakeven: 7.7 years

If you operate as a C-Corp for more than 7.7 years before sale, the cumulative corporate tax drag will exceed the QSBS exit tax savings. The conversion is most beneficial when the sale occurs as close to the 5-year minimum as possible.

Accountant’s Note

Businesses can — and routinely do — maintain two sets of books: one prepared under GAAP (or managerial accounting standards) for internal control, performance evaluation, and lender reporting, and a second prepared under the Internal Revenue Code for tax purposes. The two will often diverge on items like depreciation schedules, revenue recognition timing, and inventory valuation. When modeling a C-Corp conversion, it is the tax books that determine the corporate tax liability shown above. A qualified CPA can help you understand how your specific book-to-tax differences would affect the actual drag.

What is Section 1202 QSBS?

Section 1202 of the Internal Revenue Code provides a powerful incentive for investors in qualified small businesses: up to 100% of the capital gain from the sale of Qualified Small Business Stock (QSBS) can be excluded from federal income tax. To qualify, the stock must be in a domestic C-Corporation with gross assets under $50 million at the time of issuance, the corporation must be engaged in an active qualified trade or business, and the stock must be held for at least five years. The exclusion is capped at the greater of $15 million or 10 times the adjusted basis in the stock. For business owners currently operating as S-Corps or LLCs, converting to a C-Corp can unlock this benefit — but at the cost of entity-level taxation during the holding period.

Key Considerations

5-Year Holding Period

The QSBS 5-year clock starts when the C-Corp stock is issued, not when the original entity was formed. A conversion from S-Corp or LLC resets the clock. Planning the conversion well in advance of a potential sale is essential.

$50 Million Gross Asset Limit

The corporation’s aggregate gross assets must not exceed $50 million at the time the stock is issued and immediately after. If your business is growing rapidly, timing the conversion before this threshold is critical.

State Tax Conformity Varies

Not all states conform to the federal Section 1202 exclusion. Some states (like California) do not recognize the exclusion and will tax the gain at the full state rate regardless. Check your state’s conformity before relying on this strategy.

Qualified Trade or Business

Certain industries are excluded from QSBS treatment, including professional services (law, accounting, consulting, financial services, medicine), banking, insurance, farming, and hospitality. The business must be an active qualified trade or business.

C-Corp Tax Drag Is Real

Unlike an S-Corp or LLC, a C-Corp pays 21% federal tax on all operating income before distributions. This is cash that would otherwise be available to the owner. The longer you operate as a C-Corp, the more drag accumulates — eventually eliminating the QSBS benefit entirely.

Basis Stacking for Spouses

Each taxpayer can claim the $15M (or 10× basis) exclusion separately. For married co-founders or shareholders, this can effectively double the exclusion to $30 million. Proper planning with a qualified tax advisor is essential to structure ownership correctly.

Important Disclosure: This calculator provides rough estimates for educational and illustrative purposes only and does not constitute tax, legal, financial, or investment advice. Rubiq Financial Partners is not a tax advisor, CPA, or attorney, and does not provide tax preparation, legal, or accounting services. The Section 1202 QSBS exclusion is subject to complex eligibility requirements including entity type, holding period, gross asset tests, active business tests, and industry exclusions that are not fully modeled in this tool. Actual tax outcomes depend on many factors not captured here, including entity-specific tax attributes, state tax conformity, AMT considerations, accumulated earnings tax exposure, and individual taxpayer circumstances. Tax law is subject to legislative change. This tool assumes a simplified comparison and does not account for the time value of money, differences in entity-level state taxes, personal income tax on pass-through income, compensation structuring, or potential double taxation of C-Corp distributions. The C-Corp tax drag calculation is simplified and assumes constant annual operating income. Always consult with a qualified tax advisor, corporate attorney, and financial advisor before making any entity conversion or tax planning decisions. Improper QSBS structuring can result in loss of the exclusion entirely.

Considering a QSBS conversion?
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