QSBS Explained: How Section 1202 Can Make Startup Gains Tax-Free

There is a provision in the US tax code that can turn a multi-million-dollar exit into a completely tax-free event at the federal level. It has existed since 1993. It applies to a large share of venture-backed startups. And a surprising number of founders, employees and angel investors discover it only after they have done something that permanently disqualifies them.

It is Section 1202 of the Internal Revenue Code, and the stock it applies to is called Qualified Small Business Stock — QSBS.

In July 2025 the rules were substantially rewritten and expanded. This guide covers what QSBS is, the five tests that determine whether you have it, what changed in 2025, and the specific mistakes that quietly destroy eligibility years before anyone thinks about an exit.

1. What QSBS Actually Does

If your stock qualifies as QSBS and you meet the holding period, you can exclude gain on its sale from federal capital gains tax.

The excluded amount is the greater of two figures, calculated per issuer:

• A fixed dollar cap — historically $10 million, raised to $15 million for stock issued after 4 July 2025 and indexed for inflation going forward
• Ten times your adjusted basis in the stock

That second limb is the one people overlook, and it is enormous. An investor who puts $4 million into a qualifying company can shelter up to $40 million of gain. The dollar cap is a floor for small-basis holders, not a ceiling for everyone.

Critically, "per issuer" means the cap resets for each qualifying company. A serial founder with three qualifying exits has three separate caps. The exclusion also applies for alternative minimum tax purposes and is not subject to the 3.8% net investment income tax for stock acquired after 27 September 2010 — so a full exclusion really does mean zero federal tax on that gain.

2. What Changed in July 2025

The One Big Beautiful Bill Act, signed on 4 July 2025, made three structural changes to Section 1202. All three apply only to stock acquired or issued after 4 July 2025. Stock issued before that date continues under the old rules.

A tiered holding period

Previously, Section 1202 was all-or-nothing at five years. Sell at four years and eleven months and you received no exclusion at all. The new regime introduces partial exclusions:

• Three years held: 50% of gain excluded
• Four years held: 75% of gain excluded
• Five years or more: 100% of gain excluded

This is a meaningful change in behaviour, not just in arithmetic. It softens the cliff that used to make founders refuse otherwise sensible acquisition offers because of the calendar.

A higher per-issuer cap

The fixed dollar exclusion rises from $10 million to $15 million, with future inflation indexing. The 10x-basis alternative is unchanged.

A higher gross assets ceiling

The company's aggregate gross assets test — the size limit that determines whether a company can issue QSBS at all — rises from $50 million to $75 million, also indexed.

The practical effect is that companies can now issue qualifying stock for longer into their life. Under the old $50 million ceiling, a fast-growing company could cross the threshold at Series B, meaning every employee and investor who came in afterwards was permanently outside the regime. The higher ceiling extends that window by roughly a round.

3. The Five Tests Your Stock Must Pass

QSBS is not something you elect into. It is a factual determination made at the moment the stock is issued and maintained over the holding period. All of the following must be true.

Test one: the company is a domestic C corporation

This is where most disqualification happens. An LLC cannot issue QSBS. Neither can an S corporation, a partnership, or a foreign entity. If you are operating as an LLC with a plan to convert later, understand that your holding period starts at conversion and your basis is generally set by the value of what you contribute at that point — which caps your 10x-basis benefit at a level determined by the conversion, not by your original founding.

Test two: you acquired the stock at original issuance

You must have received the stock directly from the company, in exchange for money, property, or services. Buying shares from another shareholder on the secondary market does not produce QSBS in your hands, no matter how qualified the stock was for the seller.

There are narrow exceptions that preserve QSBS status on transfer — gift, inheritance, and distribution from a partnership to a partner — and these are the foundation of the planning strategies discussed below.

Test three: the gross assets test

Immediately before and immediately after the stock was issued, the company's aggregate gross assets must not have exceeded the threshold — $50 million for older stock, $75 million for stock issued after 4 July 2025. Gross assets are measured at cash plus the adjusted basis of other property, not at fair market value, which is more generous than it sounds for an asset-light software company.

Once a company crosses the threshold it can never issue QSBS again, even if assets later fall. Stock issued before the crossing remains qualified.

Test four: the active business requirement

At least 80% of the company's assets, by value, must be used in the active conduct of a qualified trade or business throughout substantially all of your holding period. Large cash balances sitting idle after a big raise can create problems here, though there is a working-capital allowance for genuinely operating businesses.

Test five: it is a qualified trade or business

Section 1202 excludes a long list of industries. A business is not qualified if its principal asset is the reputation or skill of its employees, or if it operates in:

• Health, law, engineering, architecture, accounting, actuarial science, performing arts, consulting, athletics, financial services, or brokerage services
• Banking, insurance, financing, leasing, or investing
• Farming, including raising or harvesting trees
• Mining, oil and gas, or other extraction industries eligible for depletion
• Operating a hotel, motel, restaurant, or similar business

Software, hardware, biotech products, consumer goods, manufacturing, and most technology businesses qualify comfortably. The grey zones are real, though — a digital health company that mostly delivers clinical services is in different territory from one that licenses software to providers, and fintech companies routinely have to argue about the "financial services" exclusion.

4. The Trap That Catches the Most Founders: SAFEs and Notes

This deserves its own section because it is both extremely common and almost entirely invisible until it is too late.

A SAFE is not stock. A convertible note is not stock. Neither starts your QSBS clock.

The holding period begins when the instrument converts into actual shares. The gross assets test is also applied at the conversion date, using the company's size at that moment — not at the moment the investor wired the money.

The consequences are severe and non-obvious:

• An angel who invested on a SAFE in year one and whose SAFE converts at a Series A in year three does not reach five years of holding until year eight.
• If the company has grown past the gross assets ceiling by the time the SAFE converts, the resulting stock is not QSBS at all. The investment qualifies for nothing, despite having been made when the company was tiny.

The second scenario is the painful one. A company that stacks several years of SAFEs before doing a priced round, and grows quickly in the meantime, can inadvertently strip QSBS eligibility from its earliest and most loyal backers. If your cap table is heavy with unconverted instruments, this is worth understanding before your next round — our overview of how SAFE notes work covers the mechanics of conversion in more detail.

5. Stacking, Packing, and Rollovers

Once you understand that the exclusion is per taxpayer and per issuer, the planning strategies become obvious.

Stacking

Because each taxpayer has their own cap, gifting QSBS to family members or into non-grantor trusts before an exit can multiply the total exclusion across several taxpayers. A gift preserves both the original holding period and the original basis, so the recipient inherits qualification.

Two conditions matter enormously. The trust must be a genuine non-grantor trust at the time the exclusion is claimed — a grantor trust is treated as the founder for tax purposes and claims no separate cap. And the transfer must be a real transfer, made well before a sale is under negotiation, with proper valuation and documentation.

This is also an area under active scrutiny. Treasury has signalled interest in the aggressive end of trust stacking, and anyone contemplating it should assume the rules may tighten.

Packing

Because the exclusion is the greater of the dollar cap or 10x basis, increasing basis at the time of issuance increases the ceiling. Contributing appreciated property or additional capital in exchange for stock raises basis and therefore raises the 10x limb. This is legitimate but technical, and the basis rules on property contributions have their own traps.

Section 1045 rollover

If you must sell before hitting the holding period, Section 1045 allows you to roll the proceeds into new QSBS within 60 days and carry your holding period across. This is the safety valve for founders whose company is acquired at year three, and it remains useful even under the new tiered regime if you want the full 100% exclusion rather than the 50% partial.

6. Things That Quietly Destroy Eligibility

• Company redemptions. If the company buys back a significant amount of its own stock in a window around your issuance, your stock can be disqualified. The rules cover redemptions from you or a related party within two years either side of issuance, and substantial redemptions from anyone within one year either side. Routine repurchases from departing employees can trip this if they are large enough.
• Converting to an LLC. A C corporation that converts to an LLC generally terminates QSBS status for everyone. This occasionally comes up in restructuring discussions and is almost never worth it.
• Waiting too long to convert instruments. Covered above, and the most common failure mode.
• Assuming state law follows. Several states do not conform to Section 1202. California, notably, does not — a California resident with a fully federally-excluded gain still owes California tax on all of it. Residency planning ahead of an exit is a real consideration, and one that must be genuine to survive scrutiny.
• Losing the paperwork. The burden of proving QSBS status is on you, potentially a decade after the fact. Stock purchase agreements, capitalisation records, and a company representation as to gross assets at the time of issuance are the documents that matter. Ask for them at the time.

Frequently Asked Questions

Do employees with stock options get QSBS?

Options themselves are not stock, so the clock does not start at grant. It starts on exercise, when actual shares are issued. This is a strong argument for early exercise where the strike price is low and the risk is affordable — and it interacts directly with the 83(b) election mechanics that early exercise requires. Employees who exercise at the moment of an acquisition receive stock with a holding period of zero days.

Does QSBS apply to secondary purchases in a tender offer?

No. Stock bought from an existing shareholder is not acquired at original issuance and does not qualify in the buyer's hands. The seller's own QSBS treatment on that sale is unaffected.

Can a foreign investor claim QSBS?

Section 1202 is a US federal income tax provision, so it benefits taxpayers with US federal capital gains liability. Non-resident investors generally are not subject to US tax on capital gains from stock sales in the first place, so the question is usually moot for them.

What if the company grows past $75 million after I get my stock?

That is fine. The gross assets test is measured at issuance, not at sale. Once your stock qualifies, subsequent company growth does not disqualify it — only the active business and qualified trade tests continue to apply over the holding period.

Does a SPAC merger or reverse merger preserve QSBS?

It depends entirely on structure. Some tax-free reorganisations preserve QSBS status and holding period; others terminate it. This is a question to put to counsel before signing anything, not after.

The Bottom Line

QSBS is one of the largest tax benefits available to anyone building or backing a startup, and it is almost entirely a function of decisions made years before an exit: what entity you incorporated as, when your instruments converted, whether you kept the records, and whether anyone thought about it at all.

The actions that preserve it are cheap and unglamorous — incorporate as a Delaware C corporation, convert SAFEs before you outgrow the ceiling, keep clean issuance documentation, and get a gross-assets representation from the company when you invest. The actions that destroy it are usually accidental.

Global Capital Network connects founders and investors across our network and events. If you are structuring a round or preparing for a liquidity event, talk to us — and browse our funding glossary for the terms you will meet along the way.

This article is general information, not tax or legal advice. Section 1202 is highly technical, the 2025 amendments are new, and eligibility turns on facts specific to you and your company. Work with a qualified tax adviser before relying on any of it.