QSBS: The Tax Break on Your C-Corp Shares

QSBS — Qualified Small Business Stock — is a federal tax break under Section 1202 of the Internal Revenue Code that can let founders and early investors pay $0 federal capital gains tax when they sell shares in a qualifying C-corporation. The headline version: if you hold founder stock in a domestic C-corp that meets the size and business-type tests, and you hold it long enough, you can exclude 100% of the gain on a sale, up to a per-issuer cap. For stock issued after July 4, 2025, that cap is $15 million (or 10x your basis, if larger), and the full 100% exclusion kicks in at a 5-year hold.

What is QSBS, and how can it mean ~$0 federal tax on a sale?

QSBS is a slice of the tax code that exists to reward people who fund and build small companies. When you sell stock that qualifies, Section 1202 lets you exclude the capital gain from your federal income — meaning the gain is simply not taxed, not merely deferred.

That is the difference between QSBS and almost every other startup tax move: it is an exclusion, not a delay.

A normal long-term capital gain on a stock sale is taxed at up to 20% federally, plus the 3.8% net investment income tax. On a qualifying QSBS sale, the federal tax on the excluded portion is zero. That is why founders building toward an acquisition or secondary sale care about QSBS from the day they incorporate — the structure you choose at formation decides whether the break is even available years later.

There is a ceiling. The exclusion is capped per company at the greater of $15 million (for stock issued after July 4, 2025; $10 million for older stock) or 10 times your adjusted cost basis in the stock. For a founder whose basis is near zero, the practical cap is the $15M / $10M number — still a very large tax-free sum.

Why does QSBS require a Delaware C-Corp and not an LLC?

Because Section 1202 only applies to stock in a domestic C-corporation. LLCs and S-corporations are structurally excluded — they do not issue the kind of stock the statute requires.

This is the cleanest argument for the C-Corp path.

A Wyoming LLC is the right default for a solo or bootstrapped founder — cheap to run (StableCorp's typical all-in upkeep is ~$299–$399/year) and taxed as a pass-through. But it can never produce QSBS. The moment you are raising priced rounds from US venture investors and imagining a large exit, the Delaware C-Corp becomes the structure of choice, and QSBS is a big part of why. (Not sure which entity fits? Start with our breakdown of sole proprietor vs LLC.)

Delaware specifically is the convention because investors and standard financing documents are built around Delaware corporate law — but QSBS itself only requires a domestic US C-corp, not Delaware in particular.

An LLC saves you money every year. A C-Corp can save you millions once. Which one is right depends on whether a large equity exit is the plan.

What are the requirements for stock to qualify as QSBS?

Five conditions have to line up — at the company level and at your level. Miss one and the stock is not QSBS, no matter how long you hold it.

Here is the checklist straight from the statute.

The active-business test is where founders get tripped up. Section 1202 deliberately excludes service businesses — health, law, engineering, accounting, consulting, financial services, banking, insurance, brokerage, farming, hospitality, and extractive industries among them. A software or product startup generally clears this; a solo consulting practice dressed up as a C-corp generally does not.

The size test is measured at issuance. As long as the company's aggregate gross assets were at or under the ceiling when your shares were issued, later growth past that number does not retroactively disqualify the stock you already hold — which is exactly why getting your founder stock issued early matters.

How did the 2025 One Big Beautiful Bill change QSBS?

It made QSBS meaningfully more generous, but only for stock issued after the law was signed. As of June 2026, the One Big Beautiful Bill Act — enacted July 4, 2025 — created a tiered exclusion and raised the dollar limits.

The old all-or-nothing 5-year rule still exists for older stock.

Under the new tiered regime, stock issued after July 4, 2025 can be partially excluded before the full five years are up: 50% of the gain after a 3-year hold, 75% after 4 years, and 100% after 5 years. The per-issuer cap rose from $10M to $15M, and the company-size ceiling rose from $50M to $75M in aggregate gross assets. Stock issued on or before July 4, 2025 keeps the prior rules — 100% exclusion only at the full 5-year hold, with the $10M cap and $50M asset ceiling.

For a founder incorporating today, the practical takeaway is simple: any new C-Corp stock you receive falls under the more generous post-July-2025 rules, including the earlier partial exclusions at three and four years.

What does QSBS mean for a non-resident founder of a US C-Corp?

Section 1202 is about the company and the stock, not the citizenship of the shareholder — so a non-resident founder who holds qualifying QSBS in a domestic C-corp can claim the federal exclusion the same way a US founder does. The break attaches to the stock, not to your passport.

That is the part most overseas founders do not realize.

Where it gets nuanced is your own residency. The US federal exclusion does not bind a foreign tax authority — if you are an Indian tax resident, India taxes your global income under its own rules, and you would look to the India–US DTAA and a Form 67 foreign tax credit to avoid double taxation. QSBS can zero out the US side; it does not automatically zero out the Indian side. This is general information, not tax advice.

What's the StableCorp angle most QSBS guides miss?

Every QSBS explainer tells you to form a C-Corp and start the 5-year clock. Almost none of them connect that to the unglamorous mechanics that actually make the clock valid: a clean original issuance, a real EIN, a funded US bank account, and a paper trail showing the stock was issued to you for value on a specific date.

QSBS is a date-stamped benefit, and the date only counts if the issuance is clean.

Your QSBS holding period starts the day the stock is properly issued — so a botched formation, a missing EIN, or stock that was never cleanly issued can quietly cost you the entire exclusion years later. StableCorp forms the Delaware C-Corp, files the SS-4 to get the EIN (required to open the US bank account — applications without one are rejected), and opens the bank account, so the cap-table event that starts your QSBS clock is documented from day one. See pricing.

Once the company is running, the cost of moving money becomes its own silent tax. The market default to off-ramp USDC is roughly 2.9% headline plus about 2% hidden FX markup — close to 5% effective. StableCorp runs it on compliant rails instead: for clients incorporated with us, 1.5% on-ramp and 0.5% off-ramp, a direct off-ramp to INR at 1%, and contractor payroll at 1% (volume-negotiable) — compliant purpose-code-based off-ramps with a proper paper trail, not the grey-area direct-wallet route.

QSBS can make your exit tax-free. A 5%-effective off-ramp taxes every dollar in between. Form the C-Corp clean, start the clock, and move the money on a 0.5–1% compliant rail.

Frequently asked questions

Does an LLC qualify for QSBS?

No. Section 1202 only applies to stock in a domestic C-corporation. An LLC (or an S-corp) cannot issue QSBS. Some founders convert an LLC to a C-corp before raising — but the QSBS holding period generally starts at the C-corp stock issuance, not at the LLC's founding, so the timing of that conversion matters.

How long do I have to hold QSBS to pay $0 federal tax?

More than five years for the full 100% exclusion. For stock issued after July 4, 2025, you can also exclude 50% after a 3-year hold and 75% after a 4-year hold under the One Big Beautiful Bill Act's tiered rules. Stock issued on or before that date only gets the exclusion at the full five-year mark.

How much gain can QSBS exclude?

The greater of $15 million (for stock issued after July 4, 2025; $10 million for older stock) or 10 times your adjusted cost basis in the stock, per issuing company. Founders with near-zero basis are typically capped at the dollar figure.

Does QSBS also exempt me from state tax?

Not necessarily. Section 1202 is a federal exclusion. Some states conform to it and some do not, so your state capital gains treatment depends on where you are taxed. Confirm your state's conformity with a qualified tax professional.

This article is general information, not legal or tax advice. As of June 2026, the requirements, the tiered 50/75/100% exclusions, the $15M/$10M per-issuer caps, and the $75M/$50M asset ceilings reflect Section 1202 as amended by the One Big Beautiful Bill Act; these rules are time-sensitive and were recently changed, so confirm the current text of Section 1202 and consult a qualified US tax advisor before relying on QSBS for a transaction.

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