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Updated December 2025

The QSBS $10 Million Limit: What You Can Actually Exclude

Section 1202 lets you exclude up to $10 million in capital gains from QSBS—or 10 times your basis, whichever is greater. That's per company, not lifetime.

For most startup employees who paid pennies per share, $10M is the cap. For investors who wrote bigger checks, the 10x rule can matter.

The Basic Rule

Your exclusion limit is the GREATER of:

A$10 million
OR
B10 × your adjusted basis in the stock

For most people, $10M is higher. The 10x rule only kicks in if you paid more than $1 million for your shares.

Example: You exercised options at $0.10/share, spending $10,000 total. Your 10x basis is $100,000—way below $10M. So your cap is $10M.

When the 10x Rule Actually Matters

The 10x rule benefits people who put significant capital into the company—usually investors, not employees.

Your Basis10x AmountYour Exclusion Cap
$10,000$100,000$10,000,000
$100,000$1,000,000$10,000,000
$1,000,000$10,000,000$10,000,000
$2,000,000$20,000,000$20,000,000
$5,000,000$50,000,000$50,000,000

The 10x rule helps angel investors and founders who invested real cash. Most employees who exercised options at low strike prices will be capped at $10M.

Per Company, Not Lifetime

This is crucial: the $10M limit applies to each company separately.

Example: You hold QSBS in Company A and Company B. Both exit. You can potentially exclude $10M from Company A AND $10M from Company B—$20M total.

Serial entrepreneurs and angel investors in multiple startups can benefit significantly from this structure.

What Happens Above the Cap

If your gain exceeds your exclusion limit, you pay normal capital gains tax on the excess.

Example: $15M gain with $10M cap

Total gain: $15,000,000

QSBS exclusion: -$10,000,000

Taxable gain: $5,000,000

Federal tax on $5M at 23.8%: ~$1,190,000

Still, saving $2.38M on the first $10M is significant. You're only paying tax on the portion above the cap.

Calculate Your Tax Savings

Enter your expected gain to see how much you can exclude and what you'll owe above the cap.

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Your Stock

Key Dates

Your holding period starts at EXERCISE, not grant. This is the #1 mistake people make.

Value

$

What you paid, or the value included in your income

$

Your Location

Your state at time of sale determines tax treatment

Strategies for Larger Gains

If you expect gains above $10M, there are legitimate strategies to optimize:

Gifting to family members

Each donee gets their own $10M limit. Gifting QSBS to children before a sale can multiply the exclusion. Gift tax rules apply—work with an estate planning attorney.

Stacking with spouse

Each spouse has a separate $10M limit. If you hold stock jointly or transfer to your spouse, you may be able to exclude up to $20M combined on the same company.

Charitable contributions

Donating appreciated QSBS to charity avoids capital gains entirely and provides a deduction. This works whether or not you've hit the $10M cap.

Timing matters: These strategies need to be executed before the sale. Transferring stock after a deal is signed may not work. Plan early.

Gift Stacking: How It Works

Each person who receives QSBS gets their own $10M exclusion. By gifting shares before a sale, you can multiply the family's total exclusion.

Example: $40M gain, family of four

Without gift stacking:
You exclude$10M
Taxable gain$30M
Federal tax at 23.8%~$7.14M
With gift stacking (you + spouse + 2 children):
You exclude$10M
Spouse excludes$10M
Child 1 excludes$10M
Child 2 excludes$10M
Total excluded$40M
Taxable gain$0
Tax saved~$7.14M

Critical requirements:

  • • Gifts must be completed before the sale (or binding agreement)
  • • Gift tax returns required—uses lifetime exemption or triggers gift tax
  • • Minors typically need a trust (UTMA or irrevocable)
  • • Each recipient must meet their own 5-year holding period
  • • Work with an estate planning attorney—this is complex

The Fine Print: Aggregation Rules

Related entities may be treated as one issuer for the $10M cap:

  • Parent/subsidiary relationships can aggregate
  • Members of a controlled group may share one cap
  • Stock acquired in a single transaction is aggregated

If you hold stock in multiple related entities, consult a tax advisor to understand how the caps apply.

Related Questions

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